Respuesta :

3x + 12x + 12 = 7
15x + 12 = 7
15x = -5
x = 1/3

3 (1/3) + 4y = 7
1 + 4y = 7
4y = 6
y = 1.5

3 (1/3) + 4 (1.5) = 7