V ( X + Y ) = A
V ( X - Y ) = B
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5A - 2B = 1
3A + B = 5
6A + 2B = 10
11A = 11
A = 1
3 + B = 5 ---> B = 2
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A = 1
B = 2
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V ( X + Y ) = 1
V ( X - Y ) = 2
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X + Y = 1
X - Y = 2
2X = 3 ---> X = 1.5
Y = X - 2 = ( - 0.5 )
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