15x²-47xy+28y²=0
若x² +xy+y² =14,x² -xy+y²=28求x+y的值
若x²+xy+y²=14,x²-xy+y²=28,求x+y的值
|x+2y+3|+(2x+y)²=0求x²-xy+y²
已知x²+y²=3xy且xy≠0,求x²y-²+x-²y²的
已知X²-5XY+6Y²=0,求(X²+3XY)\2Y²的值
x²+y²+4x-8y+20=0,求分式x²-y²/xy的值
x²+y²+4x-8y+20=0,求(x²-y²)÷xy的解
已知x²y²+x²+y²=10xy-16 求x,y
xy²/(x²y-y) × x²/(x²+x)=
xy²/(x²y) - y×x²/(x²+x)=
方程组{x²+y²=10(1)x²-3xy+2y²=0(2)怎么解
x²+xy=12 xy+y²=13