2x+2y=10 x-y=5 求X,Y
已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y)
已知2x-y=10,求[(x²+y²)-(x-y)²+2y(x-y)]/4y
已知X-Y/X+Y=3,求代数式2(x-y)/X+Y-3X+Y/X+Y
若(x*x+y*y)(x*x+y*y)-4x*x*y*y=0,求代数式(x*x+5xy+y*y)/(x*x+2xy+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+5=2x+4y,求【2x²-(x-y)(x-y)】【(x+y-1)(x-y
y=2x*arctan(y/x),求y‘’
已知4x=9y求(1)x+y/y (2)y-x/2x
已知x+y=10,求[(x+y)^2-(x-y)^2-2y(x-y)]÷5y的值
已知x^2+4y^2-4x+4y+5=0,求(y^4-x^4)/(y-2x)(x+y)*2x-y
若x-y/x+y=5,求x-y/2x+2y+5x+5y/3x-3y的值
如果x,y表示有理数,且x、y满足条件,|x|=5,|y|=2.|x-y|=y-x,求:x+2y的值.