作业帮【0.4x²+(3/10)y²】/【(1/4)x²-0.6y】
【0.4x²+(3/10)y²】/【(1/4)x²-0.6y】
(x+y)和(x-y)各看成一个整体,合并同类项2(x+y)-3(x-y)²+3(x+y)+4(x-y)
化简 3(X-Y)²-4(X-Y)+7(X-Y)-6(X-Y)²
因式分解：(x-y)(3x-7y)²-4(x-y)(x+y)²
(2x-y)²-4(x-y)(x+2y)
化简：（2x-y)²-4(x-y)(x+y)
已知x²+y²+5=2x+4y,求【2x²-(x-y)(x-y)】【(x+y-1)(x-y
1、y-x/x²-y²
(x+y)²+4(x+y)-5
求值(x-2y)²-4(x-2y)+2(x-2y)²-3(x-2y),其中x=-1,y=2分之1
[(y-2x)(-2x-y)-4(x-2y)²]*2y,其中x=1,y=2
若|x+2y-1|+y²+4y+4=0,求（2x-y）²-2（2x-y)(x+2y)+(x+2y)&