4x^2y+12xy+9y
4x^2y+12xy+9y
xy=-2,x+y=3,求代数式(4xy+12y)+[7x-(3xy+4y-x)]
x^2y+4xy+4y
(x-2xy)*(-xy+2y*y)-(3x*x-2xy)(x-9xy+6y*y)
因式分解 -4X^2-9Y^2+12XY
4x^2+y^2-4x+6y+10=0,4x^2-12xy+9y^2
已知4x^2+y^2-4xy-12x+6y+9=0,求x,y的关系
分解因式4x^2-12xy+9y^2-2x+3y-6
x*-2xy+3y*=9 4x*-5xy+6y*=30
化简:x-y/x+3y÷x^-y^2/x^2+6xy+9y^2-(xy/x+y)
(x^-4y^)/(x^+2xy+y^)/(x+2y)/(2x^+2xy)
解方程组2x*+2xy+4y*+x=19;x*+xy+2y*-y=9