已知x-y=8,(x+y)(x-y)=32,求x,y的值

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已知x-y=8,(x+y)(x-y)=32,求x,y的值已知x-y=8,(x+y)(x-y)=32,求x,y的值已知x-y=8,(x+y)(x-y)=32,求x,y的值因为X-Y=8.(X+Y)(X-

已知x-y=8,(x+y)(x-y)=32,求x,y的值
已知x-y=8,(x+y)(x-y)=32,求x,y的值

已知x-y=8,(x+y)(x-y)=32,求x,y的值
因为X-Y=8.(X+Y)(X-Y)=32.所以X+Y=4.列方程相加:2x=12.得X=6.则:Y=-2

x-y=8
(x+y)(x-y)=32
那么x+y=4
x-y=8,那么x=8+y
8+y+y=4
y=-2
所以x=6

由x-y=8得 x=8+y
代入(x+y)(x-y)=32得
(8+y+y)*8=32
(8+2y)*8=32
64+16y=32
16y=32-64
16y=-32
y=-2
所以x=6