已知4^x=18,8^y=128,求9y^2-x^2
已知4x=9y求(1)x+y/y (2)y-x/2x
已知x^2+4y^2-4x+8y+8=0,求x+y
已知x/y=3/2求代数式4x-9y/2x+3y
已知X.x+y.y-4x+2y+5=0,求4X.X-12X Y+9Y.y的值
已知实数x.y满足根号(x+y-8)+根号(8-x-y)=根号(3x-y-4)+根号(x-2y+7),求x,y
已知方程组4x+2y=1,20x+8y,求x,y
已知2x-y=10,求[(x²+y²)-(x-y)²+2y(x-y)]/4y
已知x/y=2,求2x(x+y)-y(x+y)/4x²-4xy+y²
已知2x+2y=-8,4x+y=15求(x-y)^-(3x+2y)^
已知x+y/y=11/8,求x-y/x+2y的值.
已知x*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值?
已知X-Y/X+Y=3,求代数式2(x-y)/X+Y-3X+Y/X+Y