Answers

2016-04-24T18:12:47+05:30
First you have to find values of x,y after that put into the formula and you will see the answer
2 5 2
2016-04-25T12:18:13+05:30
=from the equations x=4+y
=y[4+y]=21
=4y+ysquare=21
=ysquare+4y-21=0
=factorise it 
u get y=3,-7
substitute in x-y=4

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