Question

y varies directly as the square of x. When x = 1, y = 8. Find x when y = 128.

Answer 1

im thinking about proportions.. try it x(1)-->y(8) then ?(x)-->y(128)

Answer 2

The question says y varies directly as the SQUARE of x so\[y = kx^2\]

Answer 3

You can find the constant 'k' by just plugging in your original 'x' and 'y' values, then solving it for the latter 'y' value once you have the constant