2x-y=0与x+y=10

2x-y=0与x+y=10 x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 若／X+Y-9／+（2X-Y+3)=0求X与Y的值 2x-5+y/3=x+3y/4+7与10(x-y)-4(1-x)/3-y=0 求方程组的解 如果2x+y=5y(x,y不等于0),那么x与y成正比例吗?（ ） 已知关于x、y 的方程组x-y=a+3与2X+Y=5的解x、y满足x>0,y {4x-3y-10=0 3x-2y=0,{3x-4(x-y)=2 2x-3y=1,{2(x+y)-(x-y)=3 (x+y)-2(x-y)=1 2x-y=0与x+y=10组的解是多少 若x-y不等于0,2x-3y=0,则分式(10x-11y)/(x-y)的值是（）?(10x-11y)/(x-y) =[(8x-8y)+(2x-3y)]/(x-y) =8为什么8X-8Y=8？(10x-11y)/(x-y)=[(8x-8y)+(2x-3y)]/(x-y)=8+(2x-3y)]/(x-y)=8+0=8 已知Y=2X,X与Y不成比例. 2x=Y Y与X成?比例 x^2+4y^2-6x+4y+10=0,求x^4-y^4/(x+2y)(x-2y)*x+2y/xy^2+y^3除以（x^2+y^2/y)^2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) f(x,y)={12y^2,0 (x+y)^2/y^2-xy÷[-y^2+xy/(x-y)^2,x=0,y=根号10 x*x+2x+y*y-4y+5=0 x= y= 已知x>0,Y>0,如何证x^2/y+y^2/x>=x+y