Respuesta :

y varies directly with x 
⇒ y = kx where k is a constant.

Find k:
y = 6 when x = 2/3

6 = 2/3 k
k = 6 ÷ 2/3
k = 6 x 3/2
k = 9

Equation:
Equation : y = 9x

Find x:
when y = 12, 
12 = 9x 
x = 12 ÷ 9
x  = 4/3

Answer: 4/3