Respuesta :
3(4x - 7y = 28)
-2(6x - 5y = 31)
12x - 21y = 84
-12x + 10y = -62
0 - 11 y = 22
y = 22/-11
y = -2
12x - 21y = 84
12x - 21(-2) = 84
12x + 42 = 84
12x = 84 - 42
12x = 42
x = 42/12
x = 3.5
-2(6x - 5y = 31)
12x - 21y = 84
-12x + 10y = -62
0 - 11 y = 22
y = 22/-11
y = -2
12x - 21y = 84
12x - 21(-2) = 84
12x + 42 = 84
12x = 84 - 42
12x = 42
x = 42/12
x = 3.5