x+y=18 30%x+75%y=18*50%

X+Y=1830％X+75％Y=18*50％ x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 328-y/y x 100％=-18％ 化简 x / y(x+y) - y / x(x+y) = x+x+x+y+y=75 ,x+y=30 x= y= 字母代表什么数? x(x+y)(x-y)-y(y+x)(y-x)=(x-y)( )填空 x+y=18 30%x+75%y=18*50% x+x=y+30 XY=6,X+Y=18,X/Y=? {2x+y=15 x+2y=18 {x-3y=2,2x+y=18 ｛5x+2y=18,y=－x x+y=100 2×16x=18y 18x/34y=9/1 x/y=?/? x+y=45,24x+18y=960 x:18=y:13 x-y=50, 18x+6y=24 x=y x=y+3 2x+y=18