y = 8 when x = -32, what is y when x = 64?

Question

the value of y varies directly with x.

Answer 1

Direct variation is y = kx

The given numbers form one ratio expressd as y/x = 8/-32

To find when x = 64

We set up another ratio y/64

By the definition both ratios are equal 8/-32 = y/64

Multiple each side by 64.

(8/-32)64 = (y/64)64

-8*2 =y

y = -16.