x+y=5.3;2x+3y=15.35则x,y=?
x+y=5.3;2x+3y=15.35则x,y=?
若(x-y)/(x+y)=3 则(x+2y)/(6x-7y)等于
已知X-Y/X+Y=3,求代数式2(x-y)/X+Y-3X+Y/X+Y
已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y)
【2(x-y)^3-8(x-y)^2(x+y)+6y(x-y)^2】/2(x-y)^2=
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
[x(x-y)-y(x-y)+(x+y)(x-y)]÷2x其中x=2012 y=2013
若3x-5y=0,则x+y/x=(),x-y/y=(),2x-3y/2x+3y=( )
若全集I={(x,y)|x,y∈R},集合M={(x,y)|(y-3)/(x-2)},N{(x,y)|y=x=1},则(
(3x-y)^2+(3x+y)(3x-y),x=1,y=-2
x+y/2+x-y/3=6,4(x+y)-3(x-y)=-20
{(x+y)/2+(x-y)/3=6 4(x+y)-3(x-y)=-20