(108-x)/(120-x-y)=4/5怎么解

(108-x)/(120-x-y)=4/5怎么解 x+x+x+y=60 .x-y=4 X[X/（Y+X）+X/（X-Y）]=120/288 求X/Y y=x+4/x (x y=|-x.x+4x+5| (x-y) (x-2y)+(x+2y) (x-3y)-2(x-3y) (x-4y)= 7x:4y,x:y=( ):( (x-4y)(2x+y)= 5x-4y(y-x)=? 4x方y/(x-2y)(x+2y)怎么算[x方/x-2y]-4x方y/(x-2y)(x+2y)=? (x+y)(x^2+y^2)(x-y)(x^4+x^4)=? x/3=y/4,求(x*x-xy)/(x*x+y*y)的值 x-y+5x-4x= ?x-y+5x-4x= ? x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 x²+y²=108（x-y）,x,y为正整数,求x,y. {3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1 x*x+2x+y*y-4y+5=0 x= y= 如果|X|=4 |Y|=2 且|X+Y|=X+Y 求X+Y