5x+y = 10
-x-y = -2
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4x = 8
x = 2
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-x-y = -2
-2-y = -2
-y = 0
y = 0
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Check:
5x+y = 10
5(2)+0 = 10
10+0 = 10
10 = 10
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Solution : x=2, y=0