Question

Escalone e resolva o sistema:

X+y=5
2x-y=1

Answer 1

X+y=5
2x-y=1
  3x = 6 ==> x = 2
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x + y = 5 ==> y = 5 - x ==> y = 5-2 ==> y = 3 

Answer 2

X+y=5

2x-y=1 (+)

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3x = 6

x = 6/3

x = 2

x + y = 5

2+ y = 5

y = 5 - 2

y = 3