Question

x + y = 2
2x - y = 12

Answer 1

x=2-y.
x=2-(-8/3)
x= 2+8/3
x=(6+8)/3
x=14/3


2(2-y)-y=12
4-2y-y=12
3y=4-12
y= -8/3

Answer 2

x + y = 2
× = 2 - y

2x - y = 12
2.(2-y) - y = 12
4 - 2y - y = 12
-3y = 8 .(-1)
3y = -8
y = -8/3

substituindo no x:

x + (-8/3) = 2
x = 2 + 8/3
x = 14/3

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