Question

If y varies directly as x, and y is 400 when x is r and y is r when x is 4 what is the numeric constant of vanation in this relation

Answer 1

y = 10*x

Explanation:

y = kr --> 400

r = 4k

400 = k (4k) = 4k^2

k^2 = 400/4 = 100

k = sqrt(100) = 10

k = 10