Question

y varies directly as the square of x. When x = 3, y = 54. Find y when x = 8.

Answer 1

y varies directly as the square of x means:

y = kx^2 (where we aren't sure what k is yet)

You are given

y = k*3^2 = k*9 = 54
So, k = 6.

Now let x = 8

y = 6 * 8^2 = 6 * 64 = 384.

Answer 2

Make sense?

Answer 3

yup thank you:)

Answer 4

Cool.