(x-y)²=12,(x+y)=16,求x²+y²的值
已知x²-y²=12,x+y=6,求x,y的值
4/X+1/Y=2,XY=-1,求代数式4Y-X/X-2Y/(x+2y-12Y²/x-2y)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.
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x、y是实数,且x²+y²-4x-6y+12=0.求x²+y²的最值,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+
x/y=3,求x²+y²-xy/x²-y²的值.
已知x²+y²=25,x+y=7,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
已知x²-x=7,y²-y=7,若x≠y,求x+y的值