X-Y=500 (X-300)/Y*100%=120%

x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 X-Y=500 (X-300)/Y*100%=120% 化简 x / y(x+y) - y / x(x+y) = x(x+y)(x-y)-y(y+x)(y-x)=(x-y)( )填空 x+y=20,x-y=10,y= y+10x=x+y+9 10y+x=y+10x+27 (x+y)/6+(x-y)/10=1,(x+y)/6-(x-y)/10=5 {6/x+y+10/x-y=30 6/x+y-10/x-y=-1 y+y+x=10,x+y+x=8,y=?,x=? 已知|x|+x+y=10 |y|+x-y=12 求 x+y=? 已知|x|+x+y=10,|y|+x-y=12,求x+y的值 已知|x|+x+y=10,x+|y|-y=12,求x、y的值 已知/x/+x+y=10,/y/+x-y=12.求x+y的值 (x+y)(x+y-10)+25=0,且x-y=3,求x,y (x+y)(x+y-10)+25=0,且x-y=3,求x,y X+Y-8X+10Y+41=O,求X/Y-Y/X的值 x,y 满足x(x-2)-y(y-6)=-10,求x,y的值 解两道二元一次方程组.1.y=2x 10x+y=(10y+x)-362.x+y=5 50x*4=300y