｛（2x+5y)2=36 ｛5（3x+2y）=80解方程｛（2x+5y)2=36｛5（3x+2y）=80

3(x+y)+2(x-y)=36 4(x+y)-5(x-y)=2 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) x+y/2+x-y/6=5 2(x+y)-3(x-y)=-2 (x-y)/(x+y)=3求( 3x-2y-1)/(x+y-5) 4(x-y)-3(x-y)=9 5(x-y)+2(x-y)=11 3(x+y)-4(x-y)=11,2(x-y)+5(x+y)=27 6(x-y)-2(x+y)=14 3(x-y)+(x+y)=5 先化简再求值(x-y)(x-2y)+(x-2y)(x-3y)-2(x-3y)(x-4y) x=4 y=5 {(x+y)/2+(x-y)/3=1,(x+y)-5(x-y)=2.求x=?,y=? 化简:5(x-y)+2(x+y)-3(x-y) 3x+3y+2x-2y=36 4x+4y-5x-5y=2 3(x+y)+2(x-y)=36 4(x+y)-5(x-y)=2 解方程组 先化简,再求值 [2/3x - 2/x+y（x+y/3x -x-y）]*x/x-y,其中5x+3y=0 先化简,再求值:[3x-2/x+y(x+y/3x-x-y)]/(x-y/x),其中5x+3y=0 (2x+y)²+(x+3y)(x-3y)-x(5x+8y)因式分解 (2x-3y)-(5x-y) (2X-3y)-(5x-y) (2x-5y)(3x+y)