已知3x+2y=0,求[1+(2*y^2)/(x^2-y^2)][1-(2y)/(x+y)]的值
已知|2x-3y|+|3x-y-1|=0,求x,y的值.
已知:3x=8y.求(1)x+y/y (2)2x+3y/x-2y
已知x=3分之1,y=二分之一,求代数式x-(x+y)+(x+2y)-(x+3y)+...-(x+13y)的值
已知:x,y满足|2x-y|+|y-1/2|=0,求7x-3y的值.
已知3x-4y/2x+y=1/2 求x/y的值
已知x*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值?
(1)已知x+y=6,x²-y²=5,求x-y的值(2)若x+y=3,x²+y²
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=1,y≠0,求{(x+2y)²+(2x+y)(x+4y)-3(x+y)(x-y)}÷y的值.
已知x-y/x=x/x-2y(y不等于0),求x:y的值
已知4x=9y求(1)x+y/y (2)y-x/2x
已知X-Y/X+Y=3,求代数式2(x-y)/X+Y-3X+Y/X+Y