x+y=-8;xy=9
已知x-xy=8,xy-y=-9,求x+y-2xy的值
已知2x+xy=10,3y+2xy=6.求4x+8xy+9y=?
1.已知x--xy=8,xy--y=--9,求x+y--2xy的值
1\x+1\y=8\x+y,则y\xy+x\xy=?
已知x+y=12,xy=9,求(x+3xy+y)/(xy+xy)的值
已知x-y=3xy,且xy不等于0,则-3x+6xy+3y/(7x-5y)-9xy-(3x-y)
已知(8x-9)^2+2|9y-8|=0,试求(2xy-x)/(3x-2y)+(xy-2)/(2y-3x)+(x-3)/
已知x²+y²=9,xy=-3,求多项式5x²-3xy-5y²-11xy-8x&
若实数xy满足x≥y≥2,且2x²-xy-8x+2y+9=0,则根号xy的值
已知xy/x+y=2,则代数式3x-5y+8y/-x+3xy-y的值
xy=9,x-y=-3,则x平方+3xy+y平方=?
x*-2xy+3y*=9 4x*-5xy+6y*=30