Mathematics direct variation

Question

If U varies directly as the square root of V and U = 2 wjen V = 9. Find the value of V when U = 4

Answer 1

U = ksqrV

2=ksqr9 = k3

k= 2/3

U=(2/3)sqrV

4= (2/3)sqrV

sqrV = 3/2 x 4 = 6

V = 6^2 = 36 when U = 4