y varies directly as the cube of x. When y = 15, x = 4. Calculate y when x =3.

Question

I need help solving this equation.

 

Answer 1

y varies directly as the cube of x:
this means y is proportional to the cube of x.

y α x³

or

y = cx³

Where 'c' is some constant.

plug in the given x and y and solve for c, then you can plug in c and the new x and solve for y.

Give it a shot and come back with a question and your attempt at solving this problem if you're still confused.