|x+2y+3|+(2x+y)²=0求x²-xy+y²
|x+2y+3|+(2x+y)²=0求x²-xy+y²
已知X²-5XY+6Y²=0,求(X²+3XY)\2Y²的值
已知x/y=3,求x²+2xy-3y²/x²-2xy+y²
已知x/y=3,求x²+2xy-3y²/x²-xy+y²的值
x/y=2,求分式x²-xy+3y²/x²+xy+6y²
已知3x²+xy-2y²=0(x≠0,y≠0),求x/y-y/x-x²+y²/x
已知x/y=3,求x²+2xy-3y²/x²-xy+y³的值
已知(x+2)²+|x+y+5|=0,求3x²y+{-2x²y-[-2xy+(x²
已知|x+2|+(y+1²=0,求x²+(2xy-3y²)-2(x²+xy-2y
已知3x+2y=0,求代数式(x²+xy-y²)÷(x²-xy+y²)的值.
已知2x+3y=0,求代数式1.5x+4y/3x-2y 2.x²+xy-y²/x²-xy+
计算:(1).(-2xy²)*(3x²y)²