Answer:
2/9 = 0.2 repeating
3/7 = 0.428571 repeating
Step-by-step explanation:
A bookmark has an area of 18 cm the perimeter is 22 cm what are the dimensions of the bookmark
Answer:369
Step-by-step explanation:
all you have to do is multiply 18 and 22 its easy
18 x 22 = 369.
Which of the sets of ordered pairs represents a function?
A = {(−5, 5), (−2, 2), (2, −2), (5, −5)}
B = {(4, 2), (3, −2), (9, 4), (11, −3)}
Only A
Only B
Both A and B
Neither A nor B
Answer:
Both A and B
Step-by-step explanation:
A set of ordered pairs is not a function if there is a repeating output (Y value.)
Y values of A= 5, 2, -2, -5.
Y values of B= 2, -2, 4, -3.
There are no repeating outputs.
A group of 8 friends went to lunch and spent a total of $76, which included the food bill and a tip of $16. They decided to split the bill and tip evenly among themselves.
Which equations and solutions describe the situation? Select two options.
The equation StartFraction 1 over 8 EndFraction (x + 16) = StartFraction 76 over 8 EndFraction represents the situation, where x is the food bill.
The equation StartFraction 1 over 8 EndFraction (x + 16) = 76 represents the situation, where x is the food bill.
The solution x = 60 represents the total food bill.
The solution x = 60 represents each friend’s share of the food bill and tip.
The equation 8 (x + 16) = 76 represents the situation, where x is the food bill.
Answer:
Each Person:
-In tips: $2
-Food Bill: $7.50
Step-by-step explanation:
Let's find the tip amount for each person. $16 for the whole group. Each person will give in $2 for the tips, for a total of $16 in tips.
Now that tips are done, we must subtract the amount of tips from the food bill, to see how much each person pays. $76 - $16 = $60.
Divide 60 by 8 to get.. 60/8= 7.5.
With 7.5 as an answer, we can conclude that each person paid $7.50 for the food bill.
I see you need to select solutions, may I see them to help you out? The description is pretty vague..
What are the coordinates of the midpoint of the segment whose endpoints are C(−7, −10) and D(3, 9) ?
(−2, −0.5)
(−4, −1)
(−5, −9.5)
(−8.5, 3)
Answer:
(-2, -0.5)
Step-by-step explanation:
1. add the x-coordinates and then either divide by 2 or multiply by 1/2
2. add the y-coordinates and then either divide by 2 or multiply by 1/2
(-7+3)/2 = -2
(-10+9)/2 = -0.5
Have a blessed day!
I need helppppp for this question
Answer:
too small
Step-by-step explanation:
What is the missing reason in the proof?
Given: ∠ABC is a right angle, ∠DBC is a straight angle
Prove: ∠ABC ≅ ∠ABD
A horizontal line has points D, B, C. A line extends vertically from point B to point A. Angle A B C is a right angle.
definition of angle bisector
segment addition property
definition of congruent angles
transitive property
Mark this and return
We can identify that the missing reason in the proof is: Definition of Congruent angles.
How to give proof of a congruent triangle?We know that an angle measure of 90° of ∠ABC in the triangle means that it is a right angle triangle.
We also see that ∠ADB is also a right angle and is equal to 90°.
Now, since they have exactly the same measure, these angles are congruent. Then we can say that the angles are congruent and as such:
∠ABC ≅ ∠ABD
Thus, we can identify that the missing reason is: Definition of Congruent angles.
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URGENT ASAP Please answer the option b
The solution to the system of inequalities x < 2y + 3 and -2x < y + 1 is the darker region shown in the graph.
What is an equation?An equation is an expression that shows the relationship between two or more numbers and variables.
Inequality is an expression that shows the non equal comparison of two or more numbers and variables.
The solution to the system of inequalities x < 2y + 3 and -2x < y + 1 is the darker region shown in the graph.
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The system of inequalities x > 2 · y + 3 and - 2 · x < y + 1 includes the point (x, y) = (10, 0).
How to change signs of the inequalities to contain a given point.The solution area of the two inequalities given in the statement does not contain the point (x, y) = (10, 0) as we can see in the first figure.
But if we change the sign "<" for ">" in the first inequality, then the solution area includes the point mentioned above. Please see the second figure for further details.
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The cost in collars, CCC, from an airplane flight given that the average cost of a first class seat is fff dollars and the average cost of an economy seat is eee dollars is given by the equation above if all seats are sold. What is the best interpretation of 88e88e88, e as shown in the above equation
88e interprets the total cost for all the economy class seats, as all seats are sold, where 88 is the number of economy class seats and e dollars is the cost of each economy class seat.
In the question, we are given an equation, C = 24f + 88e, and are informed that the cost, C, in dollars from an airplane flight given that the average cost of a first class seat is f dollars and the average cost of an economy seat is e dollars is given by the equation above if all seats are sold.
We are asked for the interpretation about the 88e as shown in the equation.
The equation given to us is a cost equation.
A cost equation comprises of two parts:
Per unit priceNumber of units.In the given equation, we have two types of quantities:
First class seatsEconomy seatsThus, both these quantities must be having a per unit price, multiplied by the number of units sold.
Now, we are informed that e dollars is the per unit price for an economy class seat.
Thus, 88e interprets the total cost for all the economy class seats, as all seats are sold, where 88 is the number of economy class seats and e dollars is the cost of each economy class seat.
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For complete question, refer to the attachment.
Each edge of a graph is colored with one of the four colors red, blue, yellow, or green. How could you represent the edges in this graph using a variation of the adjacency matrix structure
G is the matrix representation of the four colored graph.
According to the statement
we have given that a graph is colored with one of the four colors red, blue, yellow, or green.
And we have to represent the edges of this graph using a variation of the adjacency matrix structure
So, Adjacency Matrix Structure is a way of representing a graph as a matrix of booleans (0's and 1's). A finite graph can be represented in the form of a square matrix on a computer, where the boolean value of the matrix indicates if there is a direct path between two vertices.
And in this graph representation the Adjacency Matrix Structure denoted by a matrix G.
so, there are a four colors used that's why there are 4 into 4 matrix is formed to represent the edges.
G = [tex]\left[\begin{array}{cccc}1&0&0&0\\0&1&0&0\\0&0&1&0\\0&0&0&1\end{array}\right][/tex]
And this is the matrix representation of the graph which is colored with four graphs.
So, G is the matrix representation of the four colored graph.
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How many of the list 729 positive integers are perfect squares, cubes ,or both?
Answer:
there will be 17 integers!
List :
1
4
9
16
25
36
49
64
81
100
121
144
169
196
225
256
289
They're all squares, like for example, 1^2, 2^2, 3^2, etc
Answer:
cheapt
Step-by-step explanation:
lines L, R, and S are coplanar. Suppose L is perpendicular to R and R is perpendicular to S. Is L perpendicular to S? Explain.
Answer:
No, L and S are parallel.
Step-by-step explanation:
Perpendicular lines go directly opposite from each other, making a + looking arrangement. While parallel lines go in the exact same direction, making a = looking arrangement. The only way both S and L can both be perpendicular to R is if they are both parallel to each other. An illustration by yours truly is placed below to represent it visually.
L |
_______________________________|_____
|
|
| R
|
_______________________________|_____
S |
|
Now, if this were on the outside of a sphere, then it would be totally possible to have three lines all be parallel, because they can curve with the sides of the sphere and create a triangle with all right angles.
Use the given transformation to evaluate the integral. double integral 9xy dA R , where R is the region in the first quadrant bounded by the lines y = 2 3 x and y = 3x and the hyperbolas xy = 2 3 and xy = 3; x = u/v, y = v
It looks like the boundaries of [tex]R[/tex] are the lines [tex]y=\dfrac23x [/tex] and [tex]y=3x[/tex], as well as the hyperbolas [tex]xy=\frac23[/tex] and [tex]xy=3[/tex]. Naturally, the domain of integration is the set
[tex]R = \left\{(x,y) ~:~ \dfrac{2x}3 \le y \le 3x \text{ and } \dfrac23 \le xy \le 3 \right\}[/tex]
By substituting [tex]x=\frac uv[/tex] and [tex]y=v[/tex], so [tex]xy=u[/tex], we have
[tex]\dfrac23 \le xy \le 3 \implies \dfrac23 \le u \le 3[/tex]
and
[tex]\dfrac{2x}3 \le y \le 3x \implies \dfrac{2u}{3v} \le v \le \dfrac{3u}v \implies \dfrac{2u}3 \le v^2 \le 3u \implies \sqrt{\dfrac{2u}3} \le v \le \sqrt{3u}[/tex]
so that
[tex]R = \left\{(u,v) ~:~ \dfrac23 \le u \le 3 \text{ and } \sqrt{\dfrac{2u}3 \le v \le \sqrt{3u}\right\}[/tex]
Compute the Jacobian for this transformation and its determinant.
[tex]J = \begin{bmatrix}x_u & x_v \\ y_u & y_v\end{bmatrix} = \begin{bmatrix}\dfrac1v & -\dfrac u{v^2} \\\\ 0 & 1 \end{bmatrix} \implies \det(J) = \dfrac1v[/tex]
Then the area element under this change of variables is
[tex]dA = dx\,dy = \dfrac{du\,dv}v[/tex]
and the integral transforms to
[tex]\displaystyle \iint_R 9xy \, dA = \int_{2/3}^3 \int_{\sqrt{2u/3}}^{\sqrt{3u}} \frac{dv\,du}v[/tex]
Now compute it.
[tex]\displaystyle \iint_R 9xy \, dA = \int_{2/3}^3 \ln|v|\bigg|_{v=\sqrt{2u/3}}^{v=\sqrt{3u}} \,du \\\\ ~~~~~~~~ = \int_{2/3}^3 \ln\left(\sqrt{3u}\right) - \ln\left(\sqrt{\frac{2u}3}\right) \, du \\\\ ~~~~~~~~ = \frac12 \int_{2/3}^3 \ln(3u) - \ln\left(\frac{2u}3\right) \, du \\\\ ~~~~~~~~ = \frac12 \int_{2/3}^3 \ln\left(\frac{3u}{\frac{2u}3}\right) \, du \\\\ ~~~~~~~~ = \frac12 \ln\left(\frac92\right) \int_{2/3}^3 du \\\\ ~~~~~~~~ = \frac12 \ln\left(\frac92\right) \left(3-\frac23\right) = \boxed{\frac76 \ln\left(\frac92\right)}[/tex]
Mamadou drove 168 miles in 8 hours. If he continued at the same rate, how long
would it take to travel 126 miles?
With the given rate Mamadou will take 6 hours to travel 126 miles.
What is Unitary method ?In order to solve a problem for two different values of a quantity, its unit value is first derived. This method is known as unitary method.
Given that,
The distance travelled in 8 hours is 168 miles.
In order to calculate time for 126 miles, unitary method can be used as,
The time for 168 miles is 8 hours.
Then, the time for 1 mile is 8/168 hours.
Thus, the time for 126 mile is 8/168 × 126 = 6 hours.
Hence, the time taken by Mamadou to travel 126 miles is 6 hours.
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Does this graph show a function?
Answer:
I think that is is C
Step-by-step explanation:
The Vertical Line Test determines whether or not a curve on the graph is a function. This one passes the vertical line test because no vertical line can intersect the curve more than once. I hope that helps!
The two dot plots below compare the forearm lengths of two groups of schoolchildren: Two dot plots are shown one below the other. The title for the top dot plot is Forearm Length, Group X and the title for the bottom plot is Forearm Length, Group Y. Below the line for each dot plot is written Length in inches. There are markings from 10 to 13 on each line at intervals of one. For the top line there are 4 dots above the first mark, 4 dots above the second mark, and 2 dots above the third mark. For the bottom line there are 2 dots above the second mark, 2 dots above the third mark, and 6 dots above the fourth mark. Based on the visual inspection of the dot plots, which group appears to have the longer average forearm length? Group X, because no child in the group has a forearm length longer than 12 inches. Group X, because four children in the group have the least forearm length of 10 inches. Group Y, because a child in the group has the least forearm length of 10 inches. Group Y, because six children have a forearm length longer than 12 inches.
The group that have the longer average forearm length is group Y, because six children have a forearm length longer than 12 inches.
Which group has a longer forearm length?
A dot plot is a graph that shows the frequency of a number using dots. The greater the number of dots above a number, the greater its frequency.
In group X, the highest arm length is 12 while in group Y, it is 13. This means that group Y would have longer arm lengths.
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Jeremy rides a Ferris wheel. The graph shows h, Jeremy’s height above the ground at any time during the ride.
Which inequality represents the heights shown on the graph?
The inequality that represents the height that is displayed by the graph is: 10 ≤ h ≥ 50.
How to Identify the Inequality of a Graph?In an inequality graph, we the small circle at any end is shaded or full, the inequality sign used is either "less than or equal to" or "greater than or equal to" ("≤" or "≥"). If the circle is empty or not shaded, we use "less than" or "greater than" ("<" or ">").
In the graph showing Jeremy’s height above the ground at any time during the ride, we have a full circle (shaded) starting from 10, and another on the right at 50.
This implies that the range of height is from 10 to 50. Since the circle is full (shaded), then we would use "less than or equal to" and "greater than or equal to" ("≤" and "≥") in writing the inequality that represents the height.
Thus, where h is the height, the inequality would be: 10 ≤ h ≥ 50.
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The standard deviation of the sampling distribution of the sample mean is also called?
The standard deviation of the sampling distribution of the sample mean is also called standard error of the mean.
For the given question,
Standard error is a mathematical tool used in statistics to measure variability. The standard error of the mean (SEM) measures how much discrepancy is likely in a sample's mean compared with the population mean.The SEM takes the SD and divides it by the square root of the sample size. The SEM will always be smaller than the SD.
The standard error of the mean indicates how different the population mean is likely to be from a sample mean. You can decrease the standard error by increasing the sample size.
Standard error of the mean and standard deviation are both measures of variability used to summarize sets of data. It helps you estimate how well your sample data represents the whole population by measuring the accuracy with which the sample data represents a population using standard deviation.
Hence we can conclude that the standard deviation of the sampling distribution of the sample mean is also called standard error of the mean.
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The line plot (shown in the attached image) shows the prices of sunglasses at a department store.
a. Find the mean, median, and mode.
b. Which measure best describes the data? Why?
c. Which measure might be misleading in describing the average price of sunglasses? Explain your reasoning.
Please help!!
a. The mean, median and mode for this plot are 70.8, 70 and 60 respectively.
b. Mean best represents the data for this plot.
c. When there are outliers, the mean might be a deceptive center tendency measure.
Mean, Median, and Mode
Mean = Sum of prices / Total number of sunglasses
Mean = (20 + 20 + 50 + 50 + 50 + 60 + 60 + 60 + 60 + 60 + 60 + 70 + 70 + 70 + 80 + 80 + 80 + 80 + 90 + 90 + 90 + 90 + 100 + 100 + 130) / 25
Mean = 70.8
Median is equal to (n/2 + 1) when n is an odd number.
Here, the number of sunglasses is represented by n.
⇒ (25/2 + 1)th term is the median
Median = 13th term
Median = 70
Mode is the most frequent data from the plot.
⇒ Mode = 70
Mean Being the Best Central Measure
The mean is often the ideal measure of central tendency to use when your data distribution is continuous and symmetrical, such as when your data are normally distributed. So, mean here denotes the typical cost of the sunglasses.
Misleading Measure
When there are outliers, the data mean is significantly impacted. As a result, it may be inaccurate when examining the data's average price.
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Find the value of x.
10
Q
12
x = [?]
Answer:
10
Step-by-step explanation:
It's just symmetry. You see that the geometrical construction above has been rotated, so its properties will remain the same.
8. For circle A, the circumference is 31.4 ft. What is the area? Use 3.14 for pi
314 ft²
15.7ft²
78.5 ft²
9.9 ft²
Answer:
[tex]\huge\boxed{\sf A = 78.5\ ft\²}[/tex]
Step-by-step explanation:
Circumference = C = 31.4 ft
We know that,
C = 2πrWhere, r is the radius
31.4 = 2(3.14)r
31.4 = 6.28(r)
Divide 6.28 to both sides
31.4/6.28 = r
5 ft. = r
r = 5 ft.Now,
Finding area:A = πr²
A = (3.14)(5)²
A = (3.14)(25)
A = 78.5 ft²[tex]\rule[225]{225}{2}[/tex]
A napkin is folded into an isosceles triangle, triangle ABC, and placed on a plate, as shown. The napkin has a perimeter of 38 centimeters.
The area of the plate covered by the napkin is (C) [tex]56cm^{2}[/tex].
What is an area of a triangle?
The area of a triangle is defined as the total region that is enclosed by the three sides of any particular triangle. Basically, it is equal to half of the base times height, i.e. A = 1/2 × b × h. As a result, in order to calculate the area of a triangular polygon, we must first determine its base (b) and height (h).To find the area of the plate covered by the napkin:
Given :
A napkin is folded into an isosceles triangle, triangle ABC, and placed on a plate.The napkin has a perimeter of 38 centimeters.The following steps can be used in order to determine the area of the plate covered by the napkin:
Step 1 - The formula of the perimeter of a triangle is given below:
P = a + b + c --- (1)
where a, b, and c are the length of the sides of the triangle.
Step 2 - According to the given data, the triangle is isosceles.
Therefore, the two sides are similar and the length of the base is 8 cm.
Step 3 - Now, substitute the values of the known terms in the above formula.
38 = 2L + 8
38 - 8 = 2L
L = 15 cm
Step 4 - The area of the plate covered by the napkin is given below:
[tex]A=\frac{1}{2} * 15 * 15 *Sin30[/tex]
Step 5 - Simplify the above expression.
[tex]A=56.25cm^{2}[/tex]
Rounding off to the nearest whole number, which is [tex]56cm^{2}[/tex].
Therefore, the area of the plate covered by the napkin is (C) [tex]56cm^{2}[/tex].
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The question you are looking for is here:
A napkin is folded into an isosceles triangle, triangle ABC, and placed on a plate, as shown. The napkin has a perimeter of 38 centimeters. To the nearest square centimeter, how many square centimeters of the plate is covered by the napkin?
(A) 16 square centimeters
(B) 30 square centimeters
(C) 56 square centimeters
(D) 60 square centimeters
what is the probability that random permutation of n numbers gets sorted after 1 pass of bubble sort
It means the probability of a random permutation of n numbers gets sorted after 1 pass of bubble sort is n!
According to the statement
we have to find the probability of random permutation of the N numbers.
So, according to the definition of A random permutation is a random ordering of a set of objects, that is, a permutation-valued random variable.
In this we order of select the objects randomly.
So, Let There are n−1 comparisons, so 2n−1 possible sequences of actions - swap or don't swap.
To find the permutations, start with 1,2,3,4,5 and undo a sequence.
For example, if let n=5, there are 24=16 out of 5!
which is 5! =120 that end after one round of bubble sort.
So, It means the probability of a random permutation of n numbers gets sorted after 1 pass of bubble sort is n!
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Find the equivalent expression of 20a + 28b.
Answer:
4 (5a + 7b)
Don't worry I helped my brother with this.
Solve the equation algebraically. Calculus section 1.5 of textbook
2^x + 2^-x = 5
The value of x from the given expression is [tex]\frac{5+\sqrt{29}}{2log2} \\[/tex]
Solving quadratic expressionGiven the algebraic expression below;
2^x + 2^-x = 5
This can also be expressed as:
1/2^x+ 1/2^x = 5
Let P = 2^x, such that;
P + 1/P = 5
P²-1/P = 5
P²-1 = 5P
P²-5P-1=0
On factrorizing, then;
P = [tex]\frac{5+\sqrt{29}}{2} \\[/tex]
Since 2^x = P, then;
[tex]2^x=\frac{5+\sqrt{29}}{2} \\\\xlog2=\frac{5+\sqrt{29}}{2} \\\\x=\frac{5+\sqrt{29}}{2log2} \\[/tex]
Hence the value of x from the given expression is [tex]\frac{5+\sqrt{29}}{2log2} \\[/tex]
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Right triangle J K L is shown. Line L J has a positive slope. A dotted and horizontal line is drawn to point J to form an angle of 53 degrees.
What is the measure of the angle of elevation from point L to point J?
37°
45°
53°
137°
Considering the sum of the internal angles of the triangle, the angle of elevation from point L to point J is of 37º.
What is the sum of the internal angles of a triangle?The sum of the internal angles of a triangle is of 180º.
In this problem, the angles are:
90º, 53º, x
Hence:
90 + 53 + x = 180
x = 180 - 143
x = 37º
The angle of elevation from point L to point J is of 37º.
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Answer:
53*
Step-by-step explanation:
took on edge
PLEASE HELP BRAINLIST ANSWER PLEASE
Answer:
y = -3x + 4
Step-by-step explanation:
y = mx + c
y = gradient(x intercept) + y intercept
y = -3x + 4
Parabola a can be represented using the equation (x 3)2 = y, while line b can be represented using the equation y = mx 9. isabel claims one solution to the system of two equations must always be the vertex of parabola a. which best describes the reasonableness of her claim?
Isabel is incorrect because the point of intersection between line B and parabola A that can be determined is the y-intercept of the equations, not the vertex. This can be obtained using finding y intercept of both parabolas and vertex of parabola A.
Is her claim correct?Parabola A, (x + 3)² = y = x² + 6x + 9
Parabola B, y = mx + 9
For parabola A, when x = 0, y = (0+3)²x=0, y = 9
y coordinate of parabola A is (0,9)
⇒The vertex coordinate,
(-b/2a , -(b²-4ac)/4a) = (-3,0)
For parabola B, when x = 0, y = 0 + 9x=0, y = 9
y coordinate of parabola B is (0,9)
Isabel claims one solution to the system of two equations must always be the vertex of parabola A which is wrong.
Hence Isabel is incorrect because the point of intersection between line B and parabola A that can be determined is the y-intercept of the equations, not the vertex.
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Disclaimer: The question was given incomplete on the portal. Here is the complete question.
Question: Parabola A can be represented using the equation (x + 3)2 = y, while line B can be represented using the equation y = mx + 9. Isabel claims one solution to the system of two equations must always be the vertex of parabola A. Which best describes the reasonableness of her claim?
Give the perimeter and the area of a square with sides that measure 9 cm.
Answer:
Perimeter = 36
Area = 81
Step-by-step explanation:
Perimeter of a square is side length * 4.
9*4 = 36
Area of a square is L*L,
9*9 = 81
Surface area=
Help me please thanks so much :))
Answer:
324[tex]\pi[/tex] units³
Step-by-step explanation:
Surface Area of Sphere = 4[tex]\pi[/tex]r²; where 'r' is the radius of the sphere.
4[tex]\pi[/tex]r² =
4[tex]\pi[/tex]9² =
4[tex]\pi[/tex]81 =
324[tex]\pi[/tex] units³
Answer:
324[tex]\pi[/tex] unit^2
Step-by-step explanation:
The formula for finding the surface area of a sphere is: [tex]A = 4\pi r^2[/tex]
--> A = Surface area of the sphere
--> r = Radius of the sphere
The image shows that the radius of the sphere is 9.
All we need to do is to replace r with 9.
--> A = 4[tex]\pi[/tex]9^2
--> A = 4[tex]\pi[/tex]81
--> A = 324[tex]\pi[/tex]
So that is your final answer! 324[tex]\pi[/tex] unit^2
--> It is unit^2 since it is an area, not a volume.
+ I'm leaving this as [tex]\pi[/tex], since the question is asking for the exact value, not the ones that are rounded up.
How many two digit numbers have on odd digit and one evan digit?
Answer: There are only 90 two-digit numbers. It shouldn’t take long to write them out and count them
Step-by-step explanation:
Answer:
45 numbers
Step-by-step explanation:
The 10-digit numbers are 10-99. We can manually write them out to start and see if we can find a pattern.
We can start 10-19: The numbers that have one odd digit and one even digit at 10, 12, 14, 16, 18 (since 1 is odd, we can only pick the numbers that have an even unit digit)
Next, we move on to 20-29: The numbers that follow the property are 21, 23, 25, 27, 29
Both of these examples have 5 numbers that follow the property. We can notice that all of the subsequent clusters (30-39, 40-49, 50-59, 60-69, 70-79, 80-89, 90-99) will also have 5 each. The numbers that start with an odd number will have the same unit digits as the 10-19 cluster, and the numbers that start with an even number will have the same unit digits as the 20-29 cluster. Observe:
30-39: 30, 32, 34, 36, 38
40-49: 41, 43, 45, 47, 49
50-59: 50, 52, 54, 56, 58
60-69: 61, 63, 65, 67, 69
70-79: 70, 72, 74, 76, 78
80-89: 81, 83, 85, 87, 89
90-99: 90, 92, 94, 96, 98
In all, there are 9 clusters of numbers, and each one has 5 numbers that follow the property. Therefore, the total is 9*5 or 45 numbers