Question

Y varies directly with x. y is 42 when x is 7. what is x when y is 18

Answer 1

x = 3

Explanation:

Direct variation:

y = kx

We have (7, 42).

42 = k × 7

k = 42/7 = 6

Our equation is:

y = 6x

y = 18

18 = 6x

x = 18/6 = 3

Answer: x = 3