若(5x+y)/(7x+10y)=1/2则x/y=
若7x+10y分之5x+y=1/2,则x/y=
若(x-y)/(x+y)=3 则(x+2y)/(6x-7y)等于
若3x-5y=0,则x+y/x=(),x-y/y=(),2x-3y/2x+3y=( )
若2x-3y+4=0则x(x*x-1)+x(5-x*x)-6y+7
设x>1,y>0,若x^y+x^-y=2根号2,则x^y-x^-y等于
{ x-y/7-x+y/10=1/2 {2(x-y)+5(x+y)=3
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
10/x+y+3/x-y=-5 15/x+y-2/x-y=-1(用换元法解此方程组)
1、已知x=2y,则x-5y/x+y=()
先化简再求值(x-y)(x+y)-(x-2y) 的完全平方+x(3x-5y)-(x-y)(x-2y),其中x=1/2 y
若|x+2y-1|+y²+4y+4=0,求(2x-y)²-2(2x-y)(x+2y)+(x+2y)&
若3x=7y,则y分之x= ,x:(x:y)=