Y varies directly as z^2 and y=125 when Z=5 find y when z=3

Question

A. 45

B. 75

c.25

D. 15

Answer 1

Because y varies directly with z^2

Therefore y = kz^2.

We know at y = 125 z = 5 implies

125 = k(5)^2

125/5 = k = 5

Now z = 3 so

y = 5(3)^2 = 45