若2x-y=2y-x+15 则x-y如题 还有x=()时 式子x-1/2与x-2/3互为相反数若x=-3 是方程1/3x+|m|=5的解 则m=()

(x+y)(x-y)-(x-y)^2如题 (x+y)(x-y)-(x-y)^2 x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 若x-y+z=-4,x^2-(y+z)^2=8,则x+y+z=如题 若f(x+y,y/x)=x^2-y^2,则F(X,Y)= 若(x-y)/(x+y)=3 则(x+2y)/(6x-7y)等于 若2x=3y,则(x*x+y*y)/x*x=? 如题{(X,Y)|(X+2)2+|Y-3|=0,X,Y属于R}= 如题{(X,Y)|(X+2)²+|Y-3|=0,X,Y属于R}= 若2x-y=2y-x=15,则x-y=________. 若2x-y=2y-x+15,则x-y=（ ） 计算：(x/x-y)*(y^2/x+y)-(x^4y/x^4-y^4)/x^2/x^2+y^2如题,快,十分钟发 若2/x-1/y=3,求[y/x-y/x-y(x-y/x-x+y)]/x-2y/x的值 已知(2x+2y+1)(2x+2y-1)=3 则x+y=___如题 方程组（x-2y=m x+2y=n）则x+y=如题 已知(x-y)2-2x+2y+1=0,则(x-y)^3是多少如题,要有过程! x^2-y^2=8,x-y=4,则x+y的结果是...:如题 若(z-x)2-4(x-y)(y-z)=0,求x+z-2y+2009如题 若x,y,z成等差数列,则(z-x)^2-4(x-y)(y-x)=