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

The equation is k = y/x and the value of k is  -1/2

The equation that can be used to represent direct proportion is y = kx

Where:

When k is made the subject of the formula, the equation becomes:

k = y/x

k = -4/8 = -1/2

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y = -(1/2)x

Step-by-step explanation: Direct variation of y with x means that:

y = k*x

where k is a real constant.

We know that when y = -4, the value of x is 8. So we can replace these values in the equation and find the value of k.

-4 = k*8

now we divide by 8 into both sides:

-4/8 = k*8/8 = k

-1/2 = k

So the equation is:

y = -(1/2)x

answer: r there any options?

step-by-step explanation:

circumference divided by 3.141592654 then timesthe radius twice

step-by-step explanation:

circumference divided by 3.141592654 then timesthe radius twice