若x/y=2/5,求3x-2y/5x+4y的值

已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) 若(x*x+y*y)(x*x+y*y)-4x*x*y*y=0,求代数式(x*x+5xy+y*y)/(x*x+2xy+y*y)的值 若2x-3y=0,求5x+4y/3x-2y (x-y)/(x+y)=3求( 3x-2y-1)/(x+y-5) 若x-y/x+y=5,求x-y/2x+2y+5x+5y/3x-3y的值 若x+y分之x-y=3,求式子x+y分之5(x-y)—2(x-y)分之x+y的值 若x-y分之x+y=3,求式子x+y分之5(x-y)—2（x-y）分之x+y的值 若x^5+x^4y+x^4+x+y+1=0,且3x+2y=1,求x,y的值 {(x+y)/2+(x-y)/3=1,(x+y)-5(x-y)=2.求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 若x^2+y^2+5/4=2x+y,求x^Y+y^x的值? 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 若(x-y)乘(x+y)=5,(x+y)^2=4,试求x-y的值 已知x,y>0 2x+y+3=xy 求5x+4y最小值