Respuesta :

4x - 3y = 12
x + 3y = 48
----------------add
5x = 60
x = 60/5
x = 12

x + 3y = 48
12 + 3y = 48
3y = 48 - 12
3y = 36
y = 36/3
y = 12

solution is (12,12)