若x²-y=3,则-2/3y+1/3x²+4=( )
(1)已知x+y=6,x²-y²=5,求x-y的值(2)若x+y=3,x²+y²
若x、y满足2x+y=6,x-3y=1,求7y(x-3y)²-2(3y-x)³的值
已知x²+|y+x|=x-1/4,求(3x+y)²(2x-y)²-(4x²+y&
若|x+y+4|+(x-y+2)²=0,则3x+2y=( )
若(1+X)²+Y+1的绝对值=0 则4x-3y分之2x-y等于?
若[x+y-1]+(y+3)²=0,则x-y的值为().
若|x+2y-1|+y²+4y+4=0,求(2x-y)²-2(2x-y)(x+2y)+(x+2y)&
已知x,y满足x²+y²-4x+6y+13=0则(3x+y)²-(3x+y)(3x-y)的
若(x-y)/(x+y)=3 则(x+2y)/(6x-7y)等于
{3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1
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(