(1/3x+?)(?+2y)=4y²-1/9x²
若|x+2y-1|+y²+4y+4=0,求(2x-y)²-2(2x-y)(x+2y)+(x+2y)&
先化简再求值:(x-2y)²-(x+2y)(x-2y)-(x-3y)(x-y).其中x²+9y
已知x²+|y+x|=x-1/4,求(3x+y)²(2x-y)²-(4x²+y&
因式分解 (1).(x+y)(x+y-6)+9 (2).x²-16y²-x-4y
因式分解:(1)x²+x (2)4x²-9y (3)x²y-4y
若|x+y-1|+(x-y-2)²=0,求代数式(x+2y)(x-2y)-(2x-y)(-y-2x)的值.
(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=1,y≠0,求{(x+2y)²+(2x+y)(x+4y)-3(x+y)(x-y)}÷y的值.
【(X²+Y²)-(X-Y)²+2Y(X-Y)】/4Y=1,求4X/4X²-Y&
该怎么画出y=2(x+2)²+1,y=- 3/4(x-3)²+2.y=x²-x-2,y=-
因式分解:25(x+y)²-9(x-y)²;(x+y)²-4(x+y-1).
1/2 x²y·( )=2x³y-x²y²