若x^2-4x+4+y^2-2/3y+2/9=0求x+1/y及x^2+1/y^2的值
已知4x=9y求(1)x+y/y (2)y-x/2x
已知x*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值?
若x^5+x^4y+x^4+x+y+1=0,且3x+2y=1,求x,y的值
若x=-1/4,能否确定代数式(2x-y)(2x+y)+(2x-y)(y-4x)+2y(y-3x)的值?
若|x+2y-1|+y²+4y+4=0,求(2x-y)²-2(2x-y)(x+2y)+(x+2y)&
已知3x-4y/2x+y=1/2 求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.x+y.y-4x+2y+5=0,求4X.X-12X Y+9Y.y的值
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|2x-1|+|y-2|=0,求x、y及代数式3x平方y的值
实数XY满足X*X+Y*Y+2X-4Y+1=0,求Y/(X-4)的最大值和最小值及根号下X*X+Y*Y+2X+1的最大值
4/X+1/Y=2,XY=-1,求代数式4Y-X/X-2Y/(x+2y-12Y²/x-2y)的值