Question

Given that W is directly proportional to the square of V, and W=50 when V=5 , find W when V=9 .

Answer 1

k=2 when W=50,V=5

W=162 when V=9,k=remains constant

Explanation:

W=V²

W=kV²

50=k×5²

50=k×25

50=25k

divide both sides by 25

k=2

k remains constant

W=KV²

W=2×9²

W=2×81

W=162