Explanation:
x + y = 6 ...................equation 1
x - y = 10 ..................equation 2
Solving equation 1 and 2
x + y = 6
x - y = 10
2x = 16
x = 16 /2
Therefore x = 8
Now
putting x = 8 in equation 1
8 + y = 6
y = 6 -8
y = -2
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