Answers

2015-04-30T13:18:56+05:30
X- ( y + (x(y-x))). 
X-( y + xy - x^2)
x - y - xy + x^2 
x^2 - xy + x - y
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2015-04-30T13:28:37+05:30
X-(y+(x(y-x)))
x-(y+xy-x²)
x-y-xy+x²
1(x-y)+x(-y+x)
(x+1)(x-y)
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