Question

Resolva o sistema : Método Adição

A) X+y=-3
3x+y=1

B) x+2y=12
3x-y=22

Answer 1

$(x + y= 3)( - 1) \\ 3x + y = 1 \\ - x - y = - 3 \\ 3x + y = 1 \\ 2x = - 2 \\ x = \frac{ - 2}{2} \\ x = - 1$
B)
x+2y=12
(3x-y=22)(2)
x+2y=12
6x-2y=44
7x=56
x=56/7
x=8
x+2y=12
8+2y=12
2y=12-8
y=4/2
y=2