已知x+y+16x-4y+68=0,则x+y=?求
已知x*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值?
已知:4x = 5y,求(x+y) :y
已知x*x+4x+y*y-2y+5=0,则x*x+y*y=?
已知|3x-y|+|x+y|=0,求x-y除以x*y的值.
已知4x=9y求(1)x+y/y (2)y-x/2x
已知x^2+4y^2-4x+4y+5=0,求(y^4-x^4)/(y-2x)(x+y)*2x-y
已知X.x+y.y-4x+2y+5=0,求4X.X-12X Y+9Y.y的值
已知x的平方+y的平方-8x+6y+25=0,求(x-y+4xy/x-y)(x+y-4xy/x+y)
已知x²+y²-8x+6y+25=0,求(x-y+4xy/x-y)(x+y-4xy/x+y)
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3x^2+xy-2y^2=0,求{(x+y)/(x-y)+4xy/(y^2-x^2)}/{(x+3y)*(x-y)}
已知2x-y=10,求[(x²+y²)-(x-y)²+2y(x-y)]/4y