The unit for the amount of time Emily paints is months
The total number of paintings after she completes the class will be 23
The number of paintings after five months will be 19
Number of paintings in her collection after six months will be 20
The variable for the amount of time Emily paints and the expression for the number of paintings is 14 + t
How do we determine the values?Since the time frame mentioned in the scenario is in months, the unit for the amount of time Emily paints is "months."
She already has fourteen (14) paintings, and she makes one (1) per month, after she completes the nine-month class, Emily will have 14 + 9 = 23 paintings in her collection.
After five months, Emily will have 14 + 5 = 19 paintings in her collection.
After six months, Emily will have 14 + 6 = 20 paintings in her collection.
Let t be the number of months that Emily paints. The number of paintings in her collection after t months is 14 + t.
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Answer:
your answer is d
Step-by-step explanation:
have a nice day.
the center of a circle is on the line y=2x and the line x=1 is tangent to the circle at (1,6).find the center and the radius
The radius and the center of the circle are 4 units and (1,2), respectively
How to determine the center and the radius?The center of the circle is on
y = 2x and x = 1
Substitute x = 1 in y = 2x
y = 2 * 1
Evaluate
y = 2
This means that the center is
Center = (1, 2)
Also, we have the point of tangency to be:
(x, y) = (1, 6)
This point and the center have the same x-coordinate.
So, the distance between this point and the center is
d = 6 - 2
d = 4
This represents the radius
Hence, the radius and the center of the circle are 4 units and (1,2), respectively
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Rotate the given triangle 270° counter-clockwise about the origin.
[tex]\left[\begin{array}{ccc}-1&2&2\\-1&-1&3\end{array}\right][/tex]
[tex]\left[\begin{array}{ccc}-1&[?]&[?]\\1&[?]&[?]\end{array}\right][/tex]
The rotation of the triangle [tex]\left[\begin{array}{ccc}-1&2&2\\-1&-1&3\end{array}\right][/tex] 270° counter-clockwise about the origin gives [tex]\left[\begin{array}{ccc}-1&-1&3\\1&-2&-2\end{array}\right][/tex]
What is transformation?Transformation is the movement of a point from its initial location to a new location. Types of transformation are rotation, reflection, translation and dilation.
If a point (x, y) is rotated 270° counter-clockwise about the origin, the new point is (y, -x)
The rotation of the triangle [tex]\left[\begin{array}{ccc}-1&2&2\\-1&-1&3\end{array}\right][/tex] 270° counter-clockwise about the origin gives [tex]\left[\begin{array}{ccc}-1&-1&3\\1&-2&-2\end{array}\right][/tex]
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how many 150-pound gas cylinders are uesd each year at a 500 gpm well that fequires a chlorine dosage of 1.5 mg/L?
The number of 150-pound gas cylinders are used each year for the well is 22.
Total volume of gallons used per year
V = 500 gal/min x 1 year x 525600 min/year
V = 262,800,000 gallons = 994,806,216.835 liters
Mass of the gas cylindersmass = density x volume
mass = 1.5 mg/L x 994,806,216.835 L
mass = 1,492,209,325 mg = 3289.75 lb
number of gas cylinders usedn = 3289.75 lb/150 lb
n = 21.9
n ≈ 22 gas cylinders
Thus, the number of 150-pound gas cylinders are used each year for the well is 22.
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The function g is defined below.
please help
well, when it comes to fractions or rationals, they can never have a denominator that's 0, because if that ever happens, the fraction becomes undefined, so the values of "x" or namely the domain values, that we cannot have because they make the fraction undefined are those values that make the denominator 0, we can simply get them by setting the denominator to 0 and check what's "x".
[tex]x^2-9=0\implies x^2=9\implies x=\pm\sqrt{9}\implies x=\pm 3 \\\\[-0.35em] ~\dotfill\\\\ g(x)=\cfrac{x+6}{x^2-9}\hspace{5em} x\ne \begin{cases} 3\\ -3 \end{cases}[/tex]
Which point is on the graph of f(x) = 5*?
O A. (0, 5)
O B. (0, 0)
• C. (5, 1)
O D. (1, 5)
Answer is (1,5)
The point that is on the graph of the function [tex]F(x) = 5^x[/tex] is given by:
D. (1,5).
Which points are on the graph of the function?The function is defined by:
[tex]F(x) = 5^x[/tex]
When x = 0, [tex]F(x) = 5^0 = 1[/tex], hence point (0,1) is on the graph of the function.
When x = 1, [tex]F(x) = 5^1 = 5[/tex], hence point (1,5) is on the graph of the function, which means that option D is correct.
When x = 5, [tex]F(x) = 5^5 = 3125[/tex], hence point (5,3125) is on the graph of the function.
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A stock lost 8 1/4 points on Monday and then another 2 3/4 points on Tuesday. On Wednesday, it gained 12 points.
What was the net gain or loss of the stock for these three days?
The net gain of the stock for these three days is 1 points
Net gainMonday = - 8 1/4 pointsTuesday = -2 3/4 pointsWednesday = 12 pointsNet gain / net loss = Monday + Tuesday + Wednesday
= - 8 1/4 + (-2 3/4) + 12
= - 8 1/4 - 2 3/4 + 12
= -11 + 12
Net gain = 1 point
Therefore, the net gain of the stock for these three days is 1 points
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imes A
20) A clinical trial was conducted using a new method designed to increase
the probability of conceiving a girl. As of this writing, 914 babies were
born to parents using the new method, and 877 of them were girls. Use a
(b).01 significance level to test the claim that the new method is effective in
increasing the likelihood that a baby will be a girl. Use the P-value method
and the normal distribution as an approximation to the binomial
distribution.
(10)
a. Identify the null and alternative hypothesis.
b. Compute the test statistic z.ollowenien e to jaata ni(8)
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c. What is the P-value?
d. What is the conclusion about the null hypothesis?
e. What is the final conclusion?
The test statistic is 27.8484, the p-value is 0, and the final conclusion is that the null hypothesis H is rejected.
Given that 914 babies were born to parents who used the new method, and 877 of them were girls, the significance level to test the claim that the new method is effective in increasing the likelihood of a baby being a girl, is 0.01.
The following information is provided: the sample size is N = 914, the number of favorable cases is X = 877, and the sampling ratio is
pˉ = X / N
Pˉ = 877/914
pˉ = 0.9595 and the significance level is α = 0.01
(a) Hypothesis Zero and Alternative
The following null and alternative hypotheses should be tested:
null: p = 0.5
Alternative: p> 0.5
This is equivalent to a right-tailed test, which requires a z-test for a proportion of the population.
(b) Critical Value
Based on the information provided, the significance level is α = 0.01, so the critical value for this right-tailed test is Zc = 2.3263. This can be found using Excel or the Z distribution table. Region of rejection
The rejection area for this test on the right side is Z> 2.3263
Test statistics
The z-statistic is calculated as follows:
[tex]\begin{aligned}Z&=\frac{\bar{p}-p}{\sqrt{\frac{p(1-p)}{n}}}\\ &=\frac{0.9595-0.50}{\sqrt{\frac{0.5(1-0.5)}{914}}}\\ &=\frac{0.4595}{0.0165}\\ &=27.8484\end[/tex]
(c) The p-value
The p-value is the probability that the sample results are extreme or more extreme than the sample results obtained, assuming the null hypothesis is true. In this case,
the p-value is p = P (Z> 27.8484) = 0
(d) The decision on the null hypothesis
Using the traditional method
Since we observe that Z = 27.8484> Zc = 2.3263, we conclude that the null hypothesis is rejected.
Using the p-value method
Using the approximation of the P-value: the p-value is p = 0, and since p = 0≤0.01 we conclude that the null hypothesis is rejected.
(e) Conclusion
It is concluded that the null hypothesis H is rejected. Therefore, there is sufficient evidence to state that the population proportion p is greater than 0.5, at the significance level of 0.01.
Hence, for 914 babies born to parents using the new method, of which 877 were girls, the test statistic is 27.8484, the p-value is 0, and the final conclusion is that the null hypothesis is rejected.
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The price, p, for different size orders of custom printed shirts, n, is given in the table.
Number of shirts ordered (n) 1 5 20 100
Price of order (p) $35 $75 $225 $1025
Can a linear equation be used to model the situation? If it can, what is the slope and the y-intercept of the equation?
linear: slope = 40, y-intercept = 35
linear: slope = 10, y-intercept = 25
A linear equation cannot be used.
linear: slope = 15, y-intercept = 0
Yes a Linear Equation can be used and the slope and the y-intercept of the equation are respectively; B: slope = 10, y-intercept = 25
How to Write an equation in Slope Intercept Form?
We are given the coordinates;
(n, p) = (1, 35), (5, 75), (20, 225), (100, 1025)
Now, the way to find the slope is;
m = (y2 - y1)/(x2 - x1)
m = (75 - 35)/(5 - 1)
m = 10
The equation that models this is;
(y - 35)/(x - 1) = 10
y - 35 = 10x - 10
y = 10x + 25
Thus, y-intercept is at x = 0.
y = 10(0) + 25
y = 25
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I need help with this geometry problem see the image
The coordinate of each point is just the number it corresponds to.
a) 6
b) -5
c) 9
d) 0
Suppose you were offered this choice:
ONE supersized cone for $8 or FOUR regular-sized cones for $5.
The radius of the large cone is 5 inches, and its height is 12 inches.
Each of the smaller cones has a radius of 2.5 inches and a height of 6 inches.
Does the large cone hold more ice cream, or do the four smaller cones combined?
Which is the better deal? Provide mathematical justification for your answer.
The large cone can hold more ice cream than the four smaller cones combined.
The large cone is a better deal.
What is a cone?A cone is a three-dimensional structure with a round base and a point at the top, known as the vertex.
A cone is a three-dimensional solid geometric object with a point at the top and a circular base. A cone has a vertex and one face. For a cone, there are no edges.
The radius, height, and slant height of the cone are its three constituent parts.
For the supersized cone,
Volume = π(5)(5)(12)/3 = 314.29 cubic inches
For a small cone,
Volume= π(2.5)(2.5)(6)/3 = 39.29 cubic inches
Combined volume of 4 such cones = 4*39.29 = 157.16 cubic inches
As the volume of the larger cone is more, thus it holds more ice cream. Also it is a better deal, as it costs less than 4 small cones.
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The graph of the parent function f(x) = x3 is translated to form the graph of g(x) = (x − 4)3 − 7. The point (0, 0) on the graph of f(x) corresponds to which point on the graph of g(x)?
(4, −7)
(−4, −7)
(4, 7)
(−4, 7)
Using translation concepts, it is found that the point (0, 0) on the graph of f(x) corresponds to point (4,-7) on g(x).
What is a translation?A translation is represented by a change in the function graph, according to operations such as multiplication or sum/subtraction in it's definition.
Considering the translations, the equivalent point is found as follows:
x - 4 = 0 -> x = 4.y = 0 - 7 -> y = -7.Hence the point (0, 0) on the graph of f(x) corresponds to point (4,-7) on g(x).
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Triangles ABC and A''B''C'' are similar. Identify the type of reflection performed and the scale factor of dilation.
The type of reflection performed and the scale factor of dilation of the diagram are; Reflection over the x-axis and a scale factor dilation of 2.
How to Identify Transformation used on diagram?From the given diagram, we are told that triangle ABC is transformed into Triangle A"B"C".
Now, we are told that both triangles are similar and as such if they are similar then, it means each corresponding side has the same ratio. Thus, there was a dilation by a scale factor of 2.
Now, the reflection that took place after the dilation would be a reflection over the x-axis.
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Find the period of the function y = 2∕3 cos(4∕7x) + 2. Question 11 options: A) 7∕2π B) 4∕7π C) 3π D) 7∕4π
The period of the function y = 2∕3 cos(4∕7x) + 2. is 7/2π
How to determine the period of the function?The function is given as:
y = 2∕3 cos(4∕7x) + 2.
The above function is a cosine function
A cosine function is represented as:
y = A cos(B(x + C)) + D
Where the period is
Period = 2π/B
By comparing the equations, we have
B = 4/7
Substitute B = 4/7 in Period = 2π/B
Period = 2π/(4/7)
Express as product
Period = 2π * 7/4
Divide 4 by 2
Period = π * 7/2
Evaluate the product
Period = 7/2π
Hence, the period of the function y = 2∕3 cos(4∕7x) + 2. is 7/2π
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Janet Lopez is establishing an investment portfolio that will include stock and bond funds. She has $720,000 to invest, and she does not want the portfolio to include more than 65% stocks. The average annual return for the stock fund she plans to invest in is 18%, whereas the average annual return for the bond fund is 6%. She further estimates that the most she could lose in the next year in the stock fund is 22%, whereas the most she could lose in the bond fund is 5%. To reduce her risk, she wants to limit her potential maximum losses to $100,000.
a. Formulate a linear programming model for this problem.
Based on the amounts that Janet Lopez has to invest in stocks and bonds, the linear programming model would be:
0.18x + 0.06y = maximized returns 0.22x + 0.05y ≤ 100,000x + y ≤ 720,000x/ y + y ≤0.65What is the linear programming model?The return on stocks (x) is 18% and the return on bonds (y) is 6%, The objective function:
= 0.18x + 0.06y
There are constraints to watch out for:
Maximum to lose on stocks is 22% and on bonds is 5% but these are to be less than the total amount of $100,000.
0.22x + 0.05y ≤ 100,000
The total amount to invest is $72,000 which means that both bonds and stocks need to be less than this amount:
x + y ≤ 720,000
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How many pounds are in112 ounces? Enter only the number. Do not include units.
There are 7 pounds in 112 ounces
How to determine the number of pounds?There is 1 pound in 16 ounces
So, the number of pounds in 112 ounces is
Pounds = 116 ounces/16 ounces
Remove the unit
Pounds = 112/16
Evaluate the quotient
Pounds = 7
Hence, there are 7 pounds in 112 ounces
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evaluate the sin, cos and tan for 120deg without using a calculator
Using equivalent angles, we have that the measures are given as follows:
[tex]\sin{120^\circ} = \frac{\sqrt{3}}{2}[/tex][tex]\cos{120^\circ} = -\frac{1}{2}[/tex][tex]\tan{120^\circ} = -\sqrt{3}[/tex]What are equivalent angles?Each angle on the second, third and fourth quadrants will have an equivalent on the first quadrant.
120º is in the second quadrant, hence the equivalent on the first quadrant is:
180º - 120º = 60º.
The sine on the second quadrant is positive, hence:
[tex]\sin{120^\circ} = \sin{60^{\circ}} = \frac{\sqrt{3}}{2}[/tex]
The cosine on the second quadrant is negative, hence:
[tex]\cos{120^\circ} = \cos{60^{\circ}} = -\frac{1}{2}[/tex]
The tangent is given by the sine divided by the cosine, hence:
[tex]\tan{120^\circ} = \frac{\sin{120^\circ}}{\cos{120^\circ}} = -\sqrt{3}[/tex]
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1. Pretend that in a certain city the number of new cases of a virus was reported to be 800 new cases on Sunday. Let’s pretend that the number of new cases grows by 15% on Monday, grows by 5% on Tuesday, and then falls 10% on Wednesday, and finally falls again 10% on Thursday.
a. What will the number of new cases be on Thursday after all of this growth and falling?
The number of new cases be on Thursday after all of this growth and falling is 956.
What is an equation?An equation is an expression that shows the relationship between two or more variables and numbers.
There are initially 800 cases, hence:
Number of cases on Monday = 1.15 * 800 = 920
Number of cases on Tuesday = 1.05 * 920 = 966
Number of cases on Wednesday = 0.9 * 966 = 869.4
Number of cases on Thursday = 1.1 * 869.4 = 956.34
The number of new cases be on Thursday after all of this growth and falling is 956.
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In the following triangle, point O is the midpoint of LM, and point P is the midpoint if LN.
Below is the proof that OP||MN. The proof is divided into four parts, where the title of each part indicates its main purpose.
Complete part D of the proof.
Part A: Prove LM/LO=2
Part B: Prove LN/LP=2
Part C: Prove LMN ~ LOP
Part D: Prove OP||MN
The complete proof for part D is given in the attached text. Hence, by the nature of the converse corresponding angle,
OP is parallel to MN. (OP ║ MN).
What is a mathematical proof?A mathematical proof is an argument that is inferential with respect to a mathematical assertion that demonstrates that the provided assumptions logically ensure the conclusion.
The complete proof for part D is given as follow:
If a transversal line "t" divides through OP and MN as given in the attached image, and SE and "T.F" are the divider of ∠QSD and ∠STM, then:
∠QSE = 1/2 ∠QSO; and
∠"STF" = 1/2 ∠STM
If the corresponding angle is ∠QST = "STF", then
QSD = "STF"
Hence, by the nature of the converse corresponding angle,
OP is parallel to MN
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in ΔWXY, m∠W = (2x - 12)°, m∠X = (2x +17)°, and m∠Y = (9x - 7)°. Find m∠X.
Answer:
45°
Step-by-step explanation:
Angles in a triangle add to 180 degrees, so
2x - 12 + 2x + 17 + 9x - 7 = 18013x - 2 = 18013x = 182x = 14So, the measure of angle X is 2(14)+17=45°
Find the measure of X
Answer:
[tex]x[/tex] = 67°
Step-by-step explanation:
As we can see in the diagram, ∠[tex]x[/tex] and the 78° angle together make up the 145° angle.
∴ [tex]x[/tex] + 78° = 145°
⇒ [tex]x[/tex] = 145° - 78°
⇒ [tex]x[/tex] = 67°
The graphs of f(x) and g(x) are shown below.
f(x) = -x g(x) =2x
Which of the following is the graph of (g-f)(x)?
[tex](g-f)(x)=g(x)-f(x)=2x-(-x)=3x[/tex]
The graph is shown in the attached image.
According to Jaxs pedometer, he walked 2.783 km while taking care of the livestock in the morning and 3.124 km taking care of the livestock in the evening.
How far did Jax walk while taking care of the livestock today?
Answer:
5.907 km
Step-by-step explanation:
2.783 km + 3.124 km = 5.907 km
Theo solved the following problem correctly for homework.
2 x + y = 7. Negative 3 x + y = 2.
What is the y-coordinate of his solution?
y = negative 3
y = negative 1
y = 1
y = 5
Answer:
y=5
Step-by-step explanation:
OK, let see, 2x+y=7, –3x+y=2:
[tex]2x + y = 7 \\ - 3x + y = 2 \\ we \: need \: to \: solve \: the \: equation \: so \\ - 2x - y = - 7 \\ - 3x + y = 2 \\ - 5x = - 5 = = > x = 1 \\ 2(1) + y = 7 = = = > y = 5[/tex]
Someone help me with this question!
Answer: [tex]160^{\circ}[/tex]
Step-by-step explanation:
By the exterior angle theorem,
[tex]4x-14+5x-182=5x-100\\\\9x-196=5x-100\\\\4x=96\\\\x=24\\\\\implies m\angle BCD=20^{\circ}\\\\\implies m\angle BCA=160^{\circ}[/tex]
[tex] \qquad \qquad \bf \huge\star \: \: \large{ \underline{Answer} } \huge \: \: \star[/tex]
Angle BCA = 160°[tex]\textsf{ \underline{\underline{Steps to solve the problem} }:}[/tex]
By Exterior angle property :
[tex]\qquad❖ \: \sf \:4x - 114 + 5x - 182 = 5x - 100[/tex]
[tex]\qquad❖ \: \sf \:9x -29 6 = 5x - 100[/tex]
[tex]\qquad❖ \: \sf \:9x - 5x = - 100 + 296[/tex]
[tex]\qquad❖ \: \sf \:4x = 96[/tex]
[tex]\qquad❖ \: \sf \:x = 24 \degree[/tex]
Next, Angle BCA = 180° - Angle BCD
( linear pair )
[ let angle BCA = y ]
[tex]\qquad❖ \: \sf \:y = 180 - (5x- 100)[/tex]
[tex]\qquad❖ \: \sf \:y = 180 - (5(24) - 100)[/tex]
[tex]\qquad❖ \: \sf \:y = 180 - (120 - 100)[/tex]
[tex]\qquad❖ \: \sf \:y = 180 - 20[/tex]
[tex]\qquad❖ \: \sf \:y = 160 \degree[/tex]
[tex] \qquad \large \sf {Conclusion} : [/tex]
Angle BCA = 160°pls help I dont understand this
Answer:
D
Step-by-step explanation:
Rewrite the expression
(10¹) ³ =
Answer:
1000
Step-by-step explanation:
If you randomly selected a British Columbia ski resort, what is the probability that it will have an annual snowfall greater than 170 inches?
The probability that it will have an annual snowfall greater than 170 inches is 0.4.
How to compute the probability?The information is incomplete and the complete question wasn't found. An overview will be given. It should be noted that a probability means the likelihood of the occurence of an event.
Probability is calculated as:
= Number of ways of achieving success/Total number of possible outcomes
Let's assume that the total number of resort is 10 and those that have more than 170 inches are 4.
In this case, the probability will be:
= 4/10
= 0.4
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The following figure shows the entire graph of a relationship.
See attached!
The correct answer is Yes. The graph represents a function. The function given is: F(x) = y(-5). Note that the value of x is zero.
What is the graph of a function?A function's graph is the set of all points in the plane of the form (x, f(x)). The graph of f might similarly be defined as the graph of the equation y = f. (x).
Thus, the correct answer or function represented in the graph is f(x) = y(-5)
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A tank originally contains 100 gallon of fresh water. Then water containing 0.5 Lb of salt per gallon is pourd into the tank at a rate of 2 gal/minute, and the mixture is allowed to leave at the same rate. After 10 minute the process is stopped, and fresh water is poured into the tank at a rate of 2 gal/min, with the mixture again leaving at the same rate. Find the amount of salt in the tank at end of an additional 10 minutes.
Let [tex]S(t)[/tex] denote the amount of salt (in lbs) in the tank at time [tex]t[/tex] min up to the 10th minute. The tank starts with 100 gal of fresh water, so [tex]S(0)=0[/tex].
Salt flows into the tank at a rate of
[tex]\left(0.5\dfrac{\rm lb}{\rm gal}\right) \left(2\dfrac{\rm gal}{\rm min}\right) = 1\dfrac{\rm lb}{\rm min}[/tex]
and flows out with rate
[tex]\left(\dfrac{S(t)\,\rm lb}{100\,\mathrm{gal} + \left(2\frac{\rm gal}{\rm min} - 2\frac{\rm gal}{\rm min}\right)t}\right) \left(2\dfrac{\rm gal}{\rm min}\right) = \dfrac{S(t)}{50} \dfrac{\rm lb}{\rm min}[/tex]
Then the net rate of change in the salt content of the mixture is governed by the linear differential equation
[tex]\dfrac{dS}{dt} = 1 - \dfrac S{50}[/tex]
Solving with an integrating factor, we have
[tex]\dfrac{dS}{dt} + \dfrac S{50} = 1[/tex]
[tex]\dfrac{dS}{dt} e^{t/50}+ \dfrac1{50}Se^{t/50} = e^{t/50}[/tex]
[tex]\dfrac{d}{dt} \left(S e^{t/50}\right) = e^{t/50}[/tex]
By the fundamental theorem of calculus, integrating both sides yields
[tex]\displaystyle S e^{t/50} = Se^{t/50}\bigg|_{t=0} + \int_0^t e^{u/50}\, du[/tex]
[tex]S e^{t/50} = S(0) + 50(e^{t/50} - 1)[/tex]
[tex]S = 50 - 50e^{-t/50}[/tex]
After 10 min, the tank contains
[tex]S(10) = 50 - 50e^{-10/50} = 50 \dfrac{e^{1/5}-1}{e^{1/5}} \approx 9.063 \,\rm lb[/tex]
of salt.
Now let [tex]\hat S(t)[/tex] denote the amount of salt in the tank at time [tex]t[/tex] min after the first 10 minutes have elapsed, with initial value [tex]\hat S(0)=S(10)[/tex].
Fresh water is poured into the tank, so there is no salt inflow. The salt that remains in the tank flows out at a rate of
[tex]\left(\dfrac{\hat S(t)\,\rm lb}{100\,\mathrm{gal}+\left(2\frac{\rm gal}{\rm min}-2\frac{\rm gal}{\rm min}\right)t}\right) \left(2\dfrac{\rm gal}{\rm min}\right) = \dfrac{\hat S(t)}{50} \dfrac{\rm lb}{\rm min}[/tex]
so that [tex]\hat S[/tex] is given by the differential equation
[tex]\dfrac{d\hat S}{dt} = -\dfrac{\hat S}{50}[/tex]
We solve this equation in exactly the same way.
[tex]\dfrac{d\hat S}{dt} + \dfrac{\hat S}{50} = 0[/tex]
[tex]\dfrac{d\hat S}{dt} e^{t/50} + \dfrac1{50}\hat S e^{t/50} = 0[/tex]
[tex]\dfrac{d}{dt} \left(\hat S e^{t/50}\right) = 0[/tex]
[tex]\hat S e^{t/50} = \hat S(0)[/tex]
[tex]\hat S = 50 \dfrac{e^{1/5}-1}{e^{1/5}} e^{-t/50}[/tex]
After another 10 min, the tank has
[tex]\hat S(10) = 50 \dfrac{e^{1/5}-1}{e^{1/5}} e^{-1/5} = 50 \dfrac{e^{1/5}-1}{e^{2/5}} \approx \boxed{7.421}[/tex]
lb of salt.
Micheal solved this inequality as shown: step 1: -6(x + 3) + 10 < -2 step 2: -6x - 18 + 10 < -2 step 3: -6x - 8 < -2 step 4: -6x < 6 step 5: x > -1. what property justifies the work shown between step 3 and 4?
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Explanation:
These are the steps to focus on
step 3: -6x - 8 < -2
step 4: -6x < 6
The move from the third step to the fourth step has us adding 8 to both sides. Therefore, we use the addition property of inequality.
That property has four forms
If [tex]a > b[/tex] then [tex]a + c > b+c[/tex]If [tex]a < b[/tex] then [tex]a+c < b+c[/tex]If [tex]a \ge b[/tex] then [tex]a + c \ge b+c[/tex]If [tex]a \le b[/tex] then [tex]a+c \le b+c[/tex]It's similar to the idea of starting with a = b, then adding c to both sides to get a+c = b+c
We add the same thing to both sides to keep things balanced.