化简:2(x-y)2-3(y-x)+5(X-Y)2=3(x-y)
2(x-y)+3(x+y)2-5(x-y)-8(x+y)2-(x-y)
若3x-5y=0,则x+y/x=(),x-y/y=(),2x-3y/2x+3y=( )
(x-y)(x-2y)-(3x-2y)(x-3y)
1.((y+2x)(-2x+y)+4(x+2y)^2)/3y 2.(2(x-y)^3-8(x-y)^2(x+y)+6y(
-(5x+y)-3(2x-3y)(化简)
已知:3x=8y.求(1)x+y/y (2)2x+3y/x-2y
计算:(3x-y)2-(2x+y)2+5x(y-x)
(3x-y)²-2x(4x-5y)-(x+2y)²
10/x+y+3/x-y=-5 15/x+y-2/x-y=-1(用换元法解此方程组)
(X-3Y)(X+3Y)-(X+2Y)(X-4Y)-(2X-Y)2的平方
((x+2y)x^2+(x-y)(3x-y)-5y^2)÷2x
分式的加减:[(x/y-y/x)除以(x+y)+x(1/y-1/x)]除以1+x/y,其中x=5,y=2