Resposta :
x + y = 20 -> y = 20 - x
2y = 4/3 x
2(20 - x) = 4/3 x
6(20 - x) = 4x
120 - 6x = 4x
120 = 10x
x=12
y=20 - x = 20 - 12 = 8
2y = 4/3 x
2(20 - x) = 4/3 x
6(20 - x) = 4x
120 - 6x = 4x
120 = 10x
x=12
y=20 - x = 20 - 12 = 8