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Suppose y varies directly with x. If y = –4 when x = 8, what is the equation of direct variation? Complete the steps to write the equation of direct variation. Start with the equation of direct variation y = kx. Substitute in the given values for x and y to get . Solve for k to get . Write the direct variation equation with the value found for k. The equation is

User Tharen
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2 Answers

5 votes

Answer:

y = -1/2 x

Explanation:

Follow the directions "Complete the steps to write the equation of direct variation. Start with the equation of direct variation y = kx. Substitute in the given values for x and y to get . Solve for k to get . Write the direct variation equation with the value found for k."

y = kx substitute y = -4 and x = 8.

-4 = k*8

-4/8 = k

-1/2 = k

So the equation is y = -1/2(x).

User Kryszal
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4 votes

Answer:

1. Start with the equation of direct variation y = kx.

2.Substitute in the given values for x and y to get: -4=k(8)

3. Solve for k to get: -1/2

4. Write the direct variation equation with the value found for k. The equation is: y=(-1/2)x

Explanation:

I just did it on e2020

User Karty
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