SOLUTION: Suppose z varies directly with x and inversely with the square of y. When x=9, y=5, and z=36, find the equation of variation. I started by using the formula z=kx/y^2 36=k(9)

Algebra ->  Expressions-with-variables -> SOLUTION: Suppose z varies directly with x and inversely with the square of y. When x=9, y=5, and z=36, find the equation of variation. I started by using the formula z=kx/y^2 36=k(9)      Log On


   

Question 438170: Suppose z varies directly with x and inversely with the square of y. When x=9, y=5, and z=36, find the equation of variation.
I started by using the formula z=kx/y^2
36=k(9)/35
but then I get confused?! Can someone please explain this to me?
Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
you wrote the equation you need

just solve it for the constant "k"

36=k(9)/35 ___ 4 = k / 35 ___ 140 = k

(z)(y^2) = 140(x)