(1)已知x+y=6,x²-y²=5,求x-y的值(2)若x+y=3,x²+y²
(1)已知x+y=6,x²-y²=5,求x-y的值(2)若x+y=3,x²+y²
若x、y满足2x+y=6,x-3y=1,求7y(x-3y)²-2(3y-x)³的值
若|x+y-1|+(x-y-2)²=0,求代数式(x+2y)(x-2y)-(2x-y)(-y-2x)的值.
已知方程组2x+y=6 x-3y=1,求7y(x-3y)²-2(3y-x)³的值
已知x,y的值满足方程组x+2y=3,x-y=-2,求x/(x-y)²+x²-y²/(x+
已知x²+y²+5=2x+4y,求【2x²-(x-y)(x-y)】【(x+y-1)(x-y
已知x² +y²+5/4=2x+y,求y-x的值
已知y-2x=0,求3x²-2y²/(x+y)(x-y)的值
已知x+3y=2,求代数式(x²-y²/x+y)-【2(x+y)】的值
已知x²+x*y=-1,x*y+y²=2,试求2x²-x*y-3y²的值
已知,x-y=5,xy=6,求(x+y)²-2x-2y+1的值
已知方程组{2x+y=6,x-3y=1,不解方程组,求7y(x-3y)²-(3y-x)²的值.