先化简在求值(x+y)²-(x-y)(x+y)-(xy)²÷(xy),其中x,y是方程组『3x+2y=7 3x+y=5}的解

先化简在求值(x+y)²-(x-y)(x+y)-(xy)²÷(xy),其中x,y是方程组『3x+2y=7 3x+y=5}的解
先化简在求值(x+y)²-(x-y)(x+y)-(xy)²÷(xy),其中x,y是方程组『3x+2y=7 3x+y=5}的解

先化简在求值(x+y)²-(x-y)(x+y)-(xy)²÷(xy),其中x,y是方程组『3x+2y=7 3x+y=5}的解
(x+y)²-(x-y)(x+y)-(xy)²÷(xy)=x²+y²+2xy-(x²-y²)-xy=2y²+xy.
方程组｛3x+2y=7 3x+y=5},1式减去2式得y=2,带入得x=1.
所以(x+y)²-(x-y)(x+y)-(xy)²÷(xy)=2y²+xy=8+2=10.

解方程组得x=1,Y=2,可知XY不等于0
化解原式=X^2+Y^2+2XY-X^2+Y^2-XY=2Y^2+XY=2*4+2=10