2(2x-3y)-3(3x+2y+1) (x=2,y=-0.5) [记得用解原式哦】要过程的,

先化简再求值(x-y)(x+y)-(x-2y) 的完全平方+x(3x-5y)-(x-y)(x-2y),其中x=1/2 y (3x+y)二次方-3(3x-y)(x+y)-(x-2y)(x+3y)要过程! 化简求值,要详细过程[(y-2x)(-2x-y)-4(x-2y)^2]÷3y,其中x=1,y=-2 化简求值,要详细过程[(y-2x)(-2x-y)-4(x-2y)²]÷3y,其中x=1,y=-3 已知X-Y/X+Y=3,求代数式2(x-y)/X+Y-3X+Y/X+Y (3x-y)^2+(3x+y)(3x-y),x=1,y=-2 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) {3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1 1奥数题x-2y/x+2y=3,求x-2y/3(x+2y)-3(x-2y)/x-2y的差 若x=-1/4,能否确定代数式(2x-y)(2x+y)+(2x-y)(y-4x)+2y(y-3x)的值? 解方程：3x+2y/4=2x+y/5=x-y+1/6要详细过程 计算(2x+y)(3x-2y) 要过程