Question

Suppose y varies directly with x. If y=4 when x=-2, find x when y=6

A. -1/3
B. 3
C. 1/3
D. -3

Answer 1

The value of x is -3

Explanation:

∵ y ∝ x ⇒ y = kx

∵ y = 4 when x = -2

∴ 4 = -2 k ⇒ k = -2

∴ y = -2 x

∵ y = 6

∴ 6 = -2 x

∴ x = 6/-2 = -3