设X,Y满足条件x-y+2>=0,x+y-4>=0,2x-y-5
设Z=X+Y,其中X,Y满足X+2Y>=0,X-Y
设实数X,Y满足条件X大于等于0,X小于等于Y,X+2Y-4小于等于,则Z=X+Y的最大值是
设x,y满足约束条件x>=0 x>=y 2x-y
设实数X,Y满足2X+Y-2>=0,X-2Y+4>=0,3X-Y
设x,y是有理数,并且x,y满足x^2+2x+y^2-4y+5=0求x+y的值
设z=2x+y,变量x,y满足条件x−4y≤−33x+5y≤25x≥1
设变量X,Y满足约束条件{X-Y+3>=0,X+Y>=0,-2
设x,y满足约束条件x>=0 y>=x 4x+3y
设Z=x+y,其中实数x,y满足不等式x+2y>=0,x-y
设z=x+y,其中实数x,y满足{x+2y>=0,x-y
设实数x,y满足条件x≥0x≤yx+2y≤3
.先化简再求值:(2x+y)(2x+y)-(2x-y)平方其中X,Y满足X平方+Y平方-2X+4Y+5=0