Suppose y varies directly with x, and y = 8 when x= -2. Find x when y = 20.

Answer 1

x = 10

Answer 2

WRONG AGAIN!

y = kx
when x = -2, y = 8
8 = -2k
k = -4, so we have
y = -4x

when y = 20
20 = -4x
x = -5