Question

resolva os sistemas
x+y=12
x-y=2

Answer 1

x + y = 12
x - y = 2
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2 x = 14
x = 14/2
x = 7
x + y = 12
7 + y = 12
y = 12 - 7
y = 5

Answer 2

X+Y=12   x-y=22   x= 14  X=14/2   X= 7   X+Y=12  7 +=12    Y=12-7   Y =5