Determine what number to multiply the first equation by to form opposite terms for the x-variable. 2/5 x + 6y = -10 –2x – 2y = 40 Multiplying the first equation by will create opposite x terms.

Answers

Answer 1

Answer: 5

Step-by-step explanation: edge 2021

Answer 2

You can use the constant which if multiplied with the coefficient of x in first equation, ends up making it negative and of equal magnitude to the coefficient of x variable in second equation.

The first equation should be multiplied by the constant 5

How to choose what quantity to multiply the first equation?

This method is actually called method of elimination to solve a system of linear equations.

We make one specific variable's coefficients of equal magnitude so that we can subtract or add the equations and eliminate that variable to make it easy to get the value of the other variable which will then help in getting the value of the first variable (if working in dual variable system).

If we have equations:

[tex]a_1x + b_1y = c_1\\a_2 x + b_2y = c_2\\[/tex]

then, if we want to eliminate variable x, then we have to multiply equation 1 with [tex]-\dfrac{a_2}{a_1}[/tex] which will make coefficient of x in first equation as  [tex]a_1 \times -\dfrac{a_2}{a_1} = -a_1[/tex]

Then adding both equation will eliminate the variable x.

We could've skipped that -ve sign and at then end, instead of adding, we could've subtracted the equations.

Using above method for getting the needed constant

The system of equation we've got is

[tex]\dfrac{2}{5}x + 6y = -10\\\\-2x -2y = 40[/tex]

Thus, we have the constant needed = [tex]-\dfrac{a_2}{a_1} = -\dfrac{-2}{2/5} = 5[/tex]

The resultant system of equation we will get is:

[tex]2x + 30y = -50\\\\-2x -2y = 40[/tex]

Thus,

The first equation should be multiplied by the constant 5

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Related Questions

answer me with step by step details please

Answers

Answer:

31 3/4 %

Step-by-step explanation:

There are 100 squares so each square is a percent.  There at 31 full squares colored and it looks like 3/4 of 1 square.

f(x) = |2x +1| +3
g(x) = −2
Find (ƒ + g)(x).

Answers

Hello!

We are going to solve the question with our given functions.

We were given:

f(x) = |2x +1| + 3g(x) = -2

Those are our two given functions, we will use those to solve for (f + g)(x).

Keep in mind that (f + g)(x) could also be written as f(x) + g(x)

With this knowledge, we can solve our question.

Solve:

(ƒ + g)(x) = f(x) + g(x)

Plug in our f(x) and g(x) functions and solve.

f(x) + g(x) = |2x +1| + 3 - 2

Simplify.

|2x +1| + 3 - 2

|2x +1| + 1

Since we can't simplify this any further, the above will be our answer.

(f + g)(x) = |2x +1| + 1

Answer:

|2x +1| + 1

What is the range of the function graphed below? A bidirectional arrow rises steeply through (negative 2, negative 8), (negative 1 point 5, negative 4), (negative 1, 0), (0, 2) and extends linearly through (2, 2), (3, 2), (4, 2), (5, 2), (6, 2) and (8, 2) on the x y coordinate plane. A. B. C. D.

Answers

Answer:

  A.  -∞ < y < 2

Step-by-step explanation:

The range is the vertical extent of the graph.

Lower limit

The arrow pointing down tells you the graph extends toward -∞.

Upper limit

The arrow pointing right suggests that y=2 is a horizontal asymptote. A graph will approach, but never cross, an asymptote. Thus, we can conclude y < 2.

Range

The range is the set of values that lie between the limits:

  -∞ < y < 2

Suppose that, for a certain mathematics class, the scores are normally distributed with a mean of 75 and a standard deviation of 9. The teacher wishes to give A's to the top 7% of the students and F's to the bottom 7%. The next 17% in either direction will be given B's and D's, with the other students receiving C's. Find the bottom cutoff for receiving an A grade. (You may need to use the standard normal distribution table. Round your answer to the nearest whole number.)

Answers

The  bottom cutoff for receiving an A grade is 88.

What is the bottom cutoff for receiving an A grade?

The bottom cutoff for receiving an A grade is found as follows:

The mean of the distribution = 75

The standard deviation = 9

The z-score for the 93% = 1.476

The score for an A grade, x = mean + z-score * standard deviation

Score for an A grade, x = 75 + 1.476 * 9

Score for an A grade, x = 88

In conclusion, the minimum score for an A grade is obtained from the mean, the z-score and the standard deviation.

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Use the permutation formula below to find the number of outcomes when n = 5 and r = 2.

Answers

[tex]nPr = \frac{n!}{(n - r)!} [/tex]

[tex]5P2 = \frac{5!}{(5 - 2)!} = \frac{5 \times 4 \times 3 \times 2 \times 1}{3 \times 2 \times 1} = 20[/tex]

If a diameter of a circle has endpoints (-3,5) and
(5, 7), then the center of the circle is

Answers

Answer:

(1 , 6)

Step-by-step explanation:

the center of the circle is the midpoint of the diameter

Which is the point of coordinates:

[tex](\frac{-3+5}{2} ,\frac{5+7}{2} )[/tex]

Then the center is the point :

[tex](1 , 6)[/tex]

[tex] \huge\mathbb{ \underline{SOLUTION :}}[/tex]

Given:

[tex]\longrightarrow\bold{(-3,5)}[/tex]

[tex]\longrightarrow\bold{(5, 7)}[/tex]

Calculate the average value between the x-coordinates of the diameter and do the same for the y-coordinates:

[tex]\longrightarrow\sf{C_x=\dfrac{-3+5}{2} = \dfrac{2}{2} =1}[/tex]

[tex]\longrightarrow\sf{C_y= \dfrac{5+7}{2} = \dfrac{12}{2} = 6 }[/tex]

[tex]\huge \mathbb{ \underline{ANSWER:}}[/tex]

[tex]\longrightarrow\sf{=(1,6)}[/tex]

Solve the following equation for y to find the slope and the y-intercept: 2y - x = 6

Answers

Step-by-step explanation:

2y - x = 6

2y = x + 6

y = (x + 6) / 2

the slope is 1 and the y int is 3

I need help with this

Answers

Answer:

361

Step-by-step explanation:

discriminant = b² - 4ac

= (21)² - 4(1)(20)

= 441 - 80

= 361

what is the slope of a line that is parallel to the line whose equation is y=4/5x-3

Answers

Answer: 4/5

Step-by-step explanation: For a line to be parallel to another line there must be two conditions true.

Condition 1: Both lines must have the same slope (i.e the same x in the form y = mx + b)

Condition 2: Both lines must have different y-intercepts (i.e different b in the form y = mx + b)

Thus, if you are looking for the slope of the line parallel to y = 4/5x - 3, we can look at condition 1, and see that the slope should also be 4/5 for the other line.

2 qts for every 50 gal of water i just want to use 15 gal of water so how much do i use

Answers

The amount of qts to use for 15 gals is 0.6qts

Proportion and ratio

Ratio are written as quotient of 2 integers

Given that 2 qts for every 50 gal of water, this is written as;

2qts = 50 gals

In order to calculate for 15gal, we will have:

x = 15gals

Take the ratio

2/x = 50/15

50x = 30

x = 3/5

x = 0.6qts

Hence the amount of qts to use for 15 gals is 0.6qts

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calcula el volumen de la siguiente figura altura 30 cm diámetro mayor 16 cm diámetro menor 4 cm

Answers

The volume of the shape will be 5652cm³.

How to calculate the volume?

The given values are:

Height = 30cm

Large diameter = 16cm: Radius = 16/2 = 8cm

Small diameter = 4cm; Radius = 4/2 = 2cm

The volume will be:

= (3.14 × 8² × 30) - (3.14 × 2² × 30)

= 6028.8 - 376.8

= 5652cm³

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The final result after substituting a value into an equation is the output.
A. true
B. false

Answers

The question is true
the answer is true also letter “a”

Solve for x. Round your answer to the nearest tenth if necessary. Figures are
not necessarily drawn to scale.
T
63°
72°
18
19
45
630
37
72°
W
45°
X
X

Answers

Answer:

18/19= X/37 because 18 and x are both between 72 and 45 degrees

Multiply 18 and 37 then divide by 19 to get answer

Step-by-step explanation:

Ashley deposits $10 000 at the end of each month for 6 times at rate of 5% compounded monthly. How much will be in her account
a. at the end of 6th month?
b. 3 months after her last deposit if rate of interest have remained level?
c. at the end of 6th months if she misses the deposit in 3rd month?
d. at the end of 6th months if she deposit $20 000 at the beginning of 1st month
e. at the end of 6th months if the rate growth to 6% from 4th months
f. Construct the deposit table for each of the above questions

Answers

The future values of Ashley's periodic deposits under the five scenarios are stated in the deposit table as follows:

Deposit Table:

Item     Initial       Periodic      Deposit    Interest    Future Value    Interest

         Deposit     Deposit        Period        Rate                                    ($)

a.      $10,000     $10,000     6 months        5%        $61,774.51      $1,774.51

b.     $10,000     $10,000     3 months        5%      $30,502.78       $502.78

c.      $10,000    $10,000     6 months        5%        $51,774.51     $1,522.42

d.    $20,000    $10,000      6 months       5%        $72,201.71     $2,201.71

e.   $10,000     $10,000     6 months       5%/6%  $60,803.78       $803.78

What is the future value?

The future value of a periodic investment represents the present value of cash flows compounded at an interest rate into the future.

The future value is computed using the FV formula or factor.

It can also be computed using an online finance calculator as follows:

Data and Calculations:

Periodic Deposit = $10,000

Investment period = 6 months

Interest rate = 5% compounded monthly

a) for illustration:

N (# of periods) = 6 months

I/Y (Interest per year) = 5%

PV (Present Value) = $0

PMT (Periodic Payment) = $10,000

Results:

FV = $61,774.51

Sum of all periodic payments = $60,000 ($10,000 x 6)

Total Interest = $1,774.51

Other Special Cases:

c) Interest on $10,000 for 3 months is $1,522.42 ($1,774.51 - $252.09).

d)                             Future Value      Interest

5% with $20,000   $82,285.04    $2,285.04

5% with  $10,000     (10,083.33)          (83.33)

Total for 6 months   $72,201.71     $2,201.71

e)                            Future Value       Interest

5% for 3 months    $30,502.78       $502.78

6% for 3 months     $30,301.00       $301.00

Total for 6 months $60,803.78      $803.78

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A ribbon is 4 m long. How many pieces each 30 cm long can be cut from the ribbon?​

Answers

Answer:

13 pieces

Step-by-step explanation:

First we convert 4m into cm :

1m = 100cm

4m = 400cm

Now we need to figure out how many 30s go into 400 :

400 ÷ 30 = 13 remainder 10

So 13 pieces can be cut from the ribbon

Hope this helped and have a good day  

Answer:

13

Step-by-step explanation:

4 meters is equal to 400 centimeters.

400/30 =  13 1/3

You don't want partial pieces, so your answer is 13

The accompanying table describes results from groups of 8 births from 8 different sets of parents. The random variable x represents the number of girls among 8 children. Complete parts​ (a) through​ (d) below.
a. Find the probability of getting exactly 6 girls in 8 births.
b. Find the probability of getting 6 or more girls in 8 births.
c. Which probability is relevant for determining whether 6 is a significantly high number of girls in 8​ births: the result from part​ (a) or part​ (b)?
d. Is 6 a significantly high number of girls in 8​ births? Why or why​ not? Use 0.05 as the threshold for a significant event.

Number of Girls x P(x)
0 0.002
1 0.016
2 0.109
3 0.199
4 0.348
5 0.199
6 0.109
7 0.016
8 0.002

Answers

The answers to the questions are

0.1090.127b is a relevant factor6 is not high

How to solve for the probability

a. From the table the probability of having 6 girls in 8 birth is given as

0.109.

b. The probability of 6 or more girls in 8 births

p(6) + p(7) + p(8)

= 0.109 + 0.016 + 0.002

= 0.127

c. The result from b is the relevant factor given that it includes the probability of getting 6, 7 and 8 girls.

D. No six is not a significantly high number of girls in 8 births. This conclusion is from the fact that 0.109 is greater than 0.05.

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POINTS, AND BRAINLIEST

Answers

The identification of parts A,B andC is illustrated below with their various reasons given.

What is an equilateral triangle?

An equilateral triangle is the triangle that has all its sides equal in length and each angle is made up of angle 60°.

Part A = The similar triangle are RGE and PBE

Part B = The triangles selected are similar because it was formed by an interception of the parallel lines of the rectangle GCPR.

Part C= All the sides of the equilateral triangle are the same therefore the distance from B to E and from P to E is the same with BP which is 225ft.

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write the expression 5x(x+9) -7(x+9) in complete factored form.

Answers

5x^2 + 45 - 7x - 63 which simplifies to 5x^2 -7x -18?
Answer:

(5x-7)(x-9)

Step-by-step explanation:

Factoring is the inverse of the distributive property. This means that we want to find the factors, not the product.

Partial Factoring

The expression we are given has already been factored to an extent. Both terms are split into 2 different factors. This was done by factoring out the greatest common factor (GCF) from both terms. In the first term, the GCF was 5x, and in the second, the GCF was -7.

Complete Factoring

Even though it was partially factored, we can factor it more. When given the situation:

a(x + y) - b(x + y)

The expression can be factored into:

(a - b)(x + y)

You can add (subtract in this case because 7 is negative) the values from outside the parentheses together. This term can then be multiplied by the value within the parentheses.

Thus, 5x(x+9) -7(x+9) can be factored into:

(5x-7)(x-9)

Remember this trick only works when both terms share a factor like (x-9).

Select the correct answer from each drop-down menu. For the figure shown, point D is a midpoint of , and point J is a midpoint of . A figure shows a double-sided arrow. The points on the left and right arrows are A, B, L, and F, G, H. The points on the upper and lower lines are C, D, E, and K, J, I. Since reflecting the points C, B, A, L, and K across line maps these points onto E, F, G, H, and I, respectively, the opposite angles are congruent. Since reflecting the points L, K, J, I, and H across line maps these points onto B, C, D, E, and F, respectively, the opposite sides and , , and and are congruent.

Answers

The first blank is BAL and FGH

The second blank is AL

The third blank is CE and KI

The fourth and final blank is GH

According to the statement

we have given a diagram in which there are some angles and from these angles we have to find that the

Which opposite angles are congruent

The opposite side of AB

With GF angle which angle are congruent

Two angles are which are opposite to each other.

So, from a diagram it is clear that The angles which are congruent with each other is BAL and FGH. Because there positions are perfectly opposite and same  to each other.

And The opposite side of AB is AL because it is present at opposite position to each other.

And with GF angle GH are congruent angles.

So, The first blank is BAL and FGH

The second blank is AL

The third blank is CE and KI

The fourth and final blank is GH

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DISCLAIMER: This question is incomplete.Please see the complete question below.
QUESTION:
Select the correct answer from each drop-down menu.

For the figure shown, point D is a midpoint of , and point J is a midpoint in figure.

Since reflecting the points C, B, A, L, and K across line maps these points onto E, F, G, H, and I, respectively, the opposite angles

are congruent. Since reflecting the points L, K, J, I, and H across line maps these points onto B, C, D, E, and F, respectively, the opposite sides are congruent.


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Consider a circle whose equation is x2 + y2 – 2x – 8 = 0. Which statements are true? Select three options.



The radius of the circle is 3 units.
The center of the circle lies on the x-axis.
The center of the circle lies on the y-axis.
The standard form of the equation is (x – 1)² + y² = 3.
The radius of this circle is the same as the radius of the circle whose equation is x² + y² = 9.

Answers

Answer:

1.The center of the circle lies on the x-axis

2.The radius of the circle is 3 units.

3.The radius of this circle is the same as the radius of the circle whose equation is x² + y² = 9.

Find the missing length indicated. need help

Answers

Step-by-step explanation:

the formula for the height in a right-angled triangle is

h = sqrt(p×q)

p and q being the segments of the Hypotenuse left and right from the point, where the height intersects with the Hypotenuse.

so, in our case

12 = sqrt(16×(x-16))

let's square this to eliminate the square root :

144 = 16×(x - 16) = 16x - 256

400 = 16x

x = 25

Given the following values, evaluate the logarithmic function. log2≈0.301, log3≈0.447, log4≈0.602, log5≈0.699, 2log(2/square root of 5)

Answers

The expression of the given logarithmic function 2log(2/√5) is; D: -0.097

How to solve Logarithmic Functions?

From logarithmic Identities, we know that;

log (x/y) = log x - log y

log (x * y) = log x + log y

Thus;

2log(2/√5) = 2[log 2 - log √5)

Now, log √5 can also be expressed as;

log √5 = ¹/₂log 5

Thus;

2log(2/√5) = 2[log 2 - ¹/₂log 5]

⇒ 2 log 2 - log 5

We are given the values;

log2≈0.301, log3≈0.447, log4≈0.602, log5≈0.699

Thus;

2log(2/√5) = 2 log 2 - log 5 = 2(0.301) - 0.699

⇒ -0.097

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Determine the current through each of the LEDs in the circuits below. Which LED will be
glowing the brightest? Which LED will be the most dim?

Answers

a. [tex]I = 6. 1[/tex] × [tex]10^-4[/tex] A

b. [tex]I = 2. 6[/tex] × [tex]10^-3[/tex] A

c. [tex]I = 0. 04[/tex] A

The LED which would glow brightest is LED C with the greatest current and voltage

The LED which would be the most dim is LED B with low voltage and consequently low current.

How to determine the current

The formula for finding current

I = V/R

Where v = voltage

R = resistance

A. V = 12V

R = 4. 7 + 15 = 19. 7 kΩ = 19700 Ω in series

[tex]I = \frac{12}{19700}[/tex]

[tex]I = 6. 1[/tex] × [tex]10^-4[/tex] A

B. V = 9V

R = 4. 7 + 1 = 4. 7 kΩ = 4700Ω in series

[tex]I = \frac{12}{4700}[/tex]

[tex]I = 2. 6[/tex] × [tex]10^-3[/tex] A

C.  V=  12V

1/R = [tex]\frac{1}{750} + \frac{1}{1200} + \frac{1}{950 }[/tex] = [tex]3. 22[/tex] × [tex]10^-3[/tex]

R = [tex]\frac{1}{3. 22 * 10 ^-3}[/tex] = 310. 56 Ω

[tex]I = \frac{12}{310. 56}[/tex]

[tex]I = 0. 04[/tex] A

It is important to note that the brightness of a bulb depends on both current and voltage depending on whether the bulb it is in parallel or series.

The LED which would glow brightest is LED C with the greatest current and voltage

The LED which would be the most dim is LED B with low voltage and consequently low current.

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Gabrielle is 12 years younger than Mikhail. The sum of their ages is 38. What is Mikhail’s age?

Answers

m + (m - 12) = 38
2m = 38 + 12 = 50
m = 50 / 2 = 25
Mikhail is 25 yo

18. Which TWO linear inequalities are shown in the
graph below?
y
A.
B.
C.
D.
E.
F.
G.
H.
y> -2
y < -2
x<-2
X > -2
x+y<1
x-y<-1
x+y>1
x-y> -1

Answers

Answer: A and H

Step-by-step explanation:

y=x+1 is shaded below and dotted, so [tex]y < x+1 \implies x-y > -1[/tex].

Also, y=-2 is dotted and shaded above, so it represents [tex]y > -2[/tex]

Off the production line, there is a 2.2% chance that a candle is defective. If the company selected 40 candles off the line, what is the standard deviation of the number of defective candles in the group?

Answers

The standard deviation of the number of defective candles in the group is 0.9277.

When a random variable X follows a binomial distribution, with the sample size n, and the proportion of success is p, then the standard deviation is calculated as:

σ = √{np(1-p)}.

In the question, we are given that off the production line, there is a 2.2% chance that a candle is defective.

We are asked if the company selected 40 candles off the line, then what is the standard deviation of the number of defective candles in the group.

Assuming the occurrence of a defective bulb as success, we get the proportion of success, p = 2.2% or 0.022, and the sample size, n = 40.

Thus, we can calculate the standard deviation of the number of defective candles in the group as:

σ = √{np(1-p),

or, σ = √{40*0.022*(1 - 0.022)} = √0.86064 = 0.9277.

Thus, the standard deviation of the number of defective candles in the group is 0.9277.

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If (one month) I make a total of 10 hours of calls at Standard hours , how much more or less will I pay for basic contact than for premium

Answers

The amount of money that you would pay less for basic contact is $15 while the amount you will pay more for premium =$465.

Calculation of the call rate per hour

From the given table in the diagram, the cost of calls made for 10 hours at Standard time=

$6 × 10 = $60

The amount of calls done for basic contact is 3 hours per month for $15 . Total cost per month = 3×15= $45

The amount of calls done for premium contact is 15 hours per month for $35 . Total cost per month = 15× 35=$525

Ordinarily, you per $60 for standard call hours. This means that,

$60 - 45 = $15 less for basic contact and

$525 - $60 = $465 more for premium.

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90°
Find mZR.
A. 30°
B. 60°
C. 120°
D. 180°
(2x)
to
P
90°
S

Answers

Answer:

120°

Step-by-step explanation:

Angles in a quadrilateral add to 360°, so

90+90+x+2x=360

180+3x=360

3x=180

x=60

So, angle R measures 120°.

the correct would be 120°

Mohinder needs to create a 5 character password. He wants each of the first, third, and fifth characters in the password to be one of the letters A to E and second and fourth characters to be one of the numerals 0 through 9. If each of the characters in the password must be unique how many passwords are possible

Answers

The number of unique passwords is 5400

How to determine the number of unique passwords?

The characteristics of the password are given as:

Number of characters = 5First, third, and fifth characters in the password = One of the letters A to ESecond and fourth characters = one of the numerals 0 through 9

Since the characters in the password must unique, we have the following possibilities

First character = Any of 5 charactersSecond characters = Any of 10 digitsThird character = Any of remaining 4 charactersFourth characters = Any of remaining 9 digitsFifth character = Any of remaining 3 characters

So, the number of unique passwords is

Password = 5 * 10 * 4 * 9 * 3

Evaluate the product

Password = 5400

Hence, the number of unique passwords is 5400

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Ali says 2 + 3 = 5, so 0.2 + 0.03 = 0.5. Is he correct? Why?​

Answers

Answer:

No he's not correct.

Step-by-step explanation:

If you look closely the 2 and the 3 in the decimals are in different sections so it would not equal 0.5

It would equal 0.23

Other Questions
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