若3^x=4,3^y=5,求3^4x+2y+1-（3^x+2y）^2的值

若2x-3y=0,求5x+4y/3x-2y 若x^5+x^4y+x^4+x+y+1=0,且3x+2y=1,求x,y的值 已知2y-x=-3,求[4y(2x-y)-2x(2x-y)]/(2x-y 已知7x+5y/2y-x=3/2,且x≠0,求X/x-4y 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) 4x-3y=5 x^2+y^2=1 求x,y 求5x-2y=x-y=4x-3y-2的解 3x+4y-5=0 x^2+y^2=1求x.y 5x+y=2,x-3y=4,求x和y, 5x+y=2 x-3y=4 求x和y 方程式计算5X-2=Y 4X+3=Y 求X.Y 已知x,y>0 2x+y+3=xy 求5x+4y最小值 若(-x+6):(x-y):(4x+y)=3:14:1,求x+y 若(-x+6):(x-y):(4x+y)=3:14:1,求x+y 若x*x-4y*y=-15,x+2y=3,求x和y的值 1.已知:x-2y=3,求[(3x+2y)(3x-2y)-(x+2y)(5x-2y)]除4x 的值 已知x-2y=2011,求[(3x+2y)(3x-2y)-(x+2y)(5x-2y)]÷4x的值. 已知x=3分之一,y=-2分之一,求代数式x-(x+y)+(x+2Y)-(x+3y)+(x+4y)...-(x+2009y)