已知:x²-xy=9,xy-y²=5,则x²-2xy+y²=(),3x²
已知x:y=3:2,求(x²+3xy)/(xy+2xy)
已知:x²-xy=9,xy-y²=5,则x²-2xy+y²=(),3x²
已知(x+1)²+|y-1|=0,求2(xy-5xy²)-(3xy²-xy)得值
已知x/y=3,求(x²+2xy-3xy²)/(x²-xy+y²)
已知X/Y=2,则X²+2XY-3Y²/X²-XY+Y²=?
已知:X+Y=-3,XY=2,X²Y+XY²
已知x+y=3 xy=-5 求x设abc=1 求x²+3xy+2y²/x²y+2xy
已知2X-3√xy-2y=0(x>0)求2x²+xy-9y²分之x²+4xy-16y
已知(x+3)+丨X-y+10丨=0 ,求5x²y-[2x²y-(3xy-xy²)-3x&
已知x²-3xy+4x=3,y²+xy-4y+7=0,则xy-1/2(x²+y²
已知x/2=y/3(xy≠0),求x²-2xy-3y²/x²-6xy-7y²的值
X²+2xy+y²/xy乘x²-2xy+y²/xy+y²=