Question

the variable x and y are directly proportional and y=2 when x=3. what is the value of y when x=9?

Answer 1

y = kx is the direct variation equation, where k is the constant of variation.
Find k.

2 = k * 3
2/3 = k

Write the variation equation.
y = (2/3)x

Plug in new value.
y = (2/3)* 9
y = 6