Question

Ajuda com sistemas
x + y = 24
x - y = 6

-x+2y=-6
2x- y =0

Answer 1

x= 6+y
substituindo:
(6+y) + y = 24
2y= 24-6
2y=18
y=9

Answer 2

A
x+y=24 x=24-y
x-y=6 ⬇
⬇ x=24-9
24-y-y=6 x=15
-2y=6-24
-2y.(-1)= -18.(-1)
2y=18
y=9

B
-x+2y= -6 2y= -6+x
2x-y= 0 ⬇
⬇ 2y= -4
2x-6+x=0 y= -2
3x= +6
x=2