已知x,y满足x+3y=5,3x+y=-1,则x-y=?

已知x,y满足x+3y=5,3x+y=-1,则x-y=? 已知x,y满足约束条件 2x+5y>=10 2x-3y>=-6 2x+y 已知x,y满足约束条件{2x+5y>=10,2x-3y>=-6,2x+y 已知实数x,y满足2x+5y>=10;2x-3y>-6;2x+y 已知:3x-5y=0,求x/y,x-y/y,x-y/x 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) 已知X和Y满足3X+4Y=2,X-Y-1/7 已知x和y满足3x+4y=2,x-y 已知实数x,y满足y=x^2+5x-4,则3x-2y最大值为 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 已知x,y满足条件5x+3y 已知实数x.y满足根号(x+y-8)+根号(8-x-y)=根号(3x-y-4)+根号(x-2y+7),求x,y 已知x=3y+2,且满足4y 已知x=3y+2,且满足4y 已知实数x,y满足约束条件x+y>3,y 已知x、y满足方程组3x+y=2013,x+3y=2012,求x-y 已知实数x,y,满足x-√x-1=√y+3-y,则x+y最大值是? 已知实数x,y满足（x+y)(x+y+3)-4=0则x+y的值是