已知|4x+3|=-5(y-1/2)²,求2(x+y)²-6(2x+y)+8(2x+y)²
已知x²+y²+5=2x+4y,求【2x²-(x-y)(x-y)】【(x+y-1)(x-y
已知x²+y²+5=2x+4y,求代数式(2x²-(x+y)(x-y))x((x+y-1)
已知x/y=2,求2x(x+y)-y(x+y)/4x²-4xy+y²
(1)已知x+y=6,x²-y²=5,求x-y的值(2)若x+y=3,x²+y²
已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y)
已知x=1/3,y=-1/2,求代数式x-(x+y)+(x+2y)-(x+3y)+(x+4y)-(x+5y)+...-(
已知x²+y²-2x+4y+5=0,求x+y
已知x² +y²+5/4=2x+y,求y-x的值
已知x²+4x+y-2y+5=0求x+2y
已知x²+y²+13-4x+6y=0,求(2x-y)²-2(2x-y)(x+2y)+(x+
已知x²+|y+x|=x-1/4,求(3x+y)²(2x-y)²-(4x²+y&
已知 (2x+3y-4)²+|x+3y+1|=0 求3x+5y的值