(-7-X+y)(-7+x+y)
(x-4y)分之(3x)+(4y-x)分之(x+y)-(x-4y)分之(7y)
若3x=7y,则y分之x= ,x:(x:y)=
若3x=7y,则y比x= ,x:(x+y)=
(3x+y)(3x-7y)
(7y-2x)-(7x-4y)
化简:2(3x-y)-3(x+7y)
已知5x=7y,x与y( )
7x+[-3x-3(x-2y)]-[5x-(2x-y)]
已知(x-y)/13=y/7,则(x+y)/y=
(x-y)7÷(y-x)4+(-x-y)8÷(x+y)5.
因式分解(X+2Y)(3X-7Y)平方-4(X+2Y)(X+Y)平方
化简,亲快啊啊急!(3x-2y)(7x-y)-(4x+3y)(x-y)