若√x^2-4x+3+|y^2-5y-6|=0 且x大于y 则x+y

若5x+3y=3x+4y=x+2y+6,则x+y=___ 因式分解(x-2y)(x-3y)+(x-4y)(x-5y)+（x-3y)(x-5y)+(x-2y)(x-4y) [2(x-y)^5-8(x-y)^2(x+y)+6y(x-y)^2]÷2(x-y)^2[2(x-y)^3-8(x-y)^2(x+y)+6y(x-y)^2]÷2(x-y)^2 若2x-3y+4=0则x（x*x-1)+x(5-x*x)-6y+7 因式分解 x-xy+3y-3x 2x+xy-y-4x+5y-6 【(4x-3y)(4x+3y)-(2x-3y)(5x+3y)]除以6x 化简(x+y)-(2x+y/2)-(3x+y/6)-(4x+y/12)-(5x+y/20)-……-(10x+y/90) 若√x^2-4x+3+|y^2-5y-6|=0 且x大于y 则x+y 2(2x+3y)(3x+2y)-(6x-y)(2x-5y) 5/4(x+y)(-x-y)^3*[-4/3(x-y)]*[-3/5(y-x)^2] x+y/2+x-y/6=5 2(x+y)-3(x-y)=-2 把(x-y)看作一个整体,化解:5(x-y)+2(x-y)-4(x-y)= 3(x-y)把(x-y)看作一个整体,化解:5(x-y)+2(x-y)-4(x-y)=3(x-y)²-4(x-y)+7(x-y)-6(x-y)²= (2x-y)(3x-4y)-2(x-y)(2x-5y)简便运算 若(x-y)/(x+y)=3 则(x+2y)/(6x-7y)等于 4x-3y/x-2y÷6y-8x/y-2x （x+y）/2- x-y/2=6 3(x+y)=4(x-y) x+y/3+x-y/2=6 4(x+y)-2(x-y)=40 {3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1