已知x,y满足x+y-6≤0,x+2y-8≤0,2x-3y-6≤0,x≥0,0≤y≤3,求(3y-12)/(x-6)的最大值和最小值.

已知x,y满足y 已知x,y满足x^2+y^2-6x+8y+25=0,求y^x的值 已知x、y满足：x^2+y^2+6x-10y+34=0,求y-x的值 已知实数x, y满足x²+y²-2x+6y+10=0,求y∧-x. 已知x,y满足x+y-2>=0,2x-y+2>=0,x 已知x,y满足约束条件：x-y+1>=0,x+y-2>=0,x 已知实数x,y满足x-y 已知实数X,Y满足{|x+y| 化简求值：已知x、y满足：x^2+y^2-4x+6y+13=0 求代数式 的值.(3x+y)^2-3(3x-y)(x+y)-(x-3y)(x+3y)急用！ 已知x.y满足(x-y-2≤0,x 2y-5≥0,y-2≤0 则3x+y/x+1得多少 已知非负实数x,y满足2x+3y-6≤0 且3x+2y-6≤0,则x+y的最大值是? 已知实数x满足x^2+2xy+y^2-(x+y)-6=0则x+y的值 已知实数x,y满足不等式组x≥0,y≥0,x+y≤1,则x^2+y^2-2x-2y的最小值 已知x、y、z满足方程组：x+y-z=6；y+z-x=2；z+x-y=0 求x、y、z的值 已知X.Y.Z满足方程组,X+y-Z=6y+z-x=2z+x-y=0求X.Y.Z的值 已知实数x、y满足x²+y²+4x-6y+13=0 已知x,y满足4x²+y²-4x-6y+10=0 已知实数x,y满足不等式组：2x-y=0,x+2y