已知x²-y²=3,求正整数x,y的值解:因为x²-y²=(x+y)(x-y)=
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
(1)已知x+y=6,x²-y²=5,求x-y的值(2)若x+y=3,x²+y²
已知方程组2x-y=10,x+2y=11,求(2x-y)³-(2x-y)²(x-3y)的值
已知非零有理数x,y满足x²-4xy+4y²=0,求x-y/x+y-y-x/x+y的值.
已知2x-y=10,求代数式[(x²+y²)-(x-y)²+2y(x-y)]÷4y的值?
已知x²+y²=25,x+y=7,求x-y的值.
已知x²-y²=12,x+y=6,求x,y的值
已知x-y=4,x²-y²=20,求x-y的值
已知x² +y²+5/4=2x+y,求y-x的值
已知x²+y²=25,x+y=7,且x>y,求x-y的值