设变量x.y满足条件3x+2y

设变量X,Y满足约束条件{X-Y+3>=0,X+Y>=0,-2 设变量x,y满足约束条件x-y>-1,x+y>1,3x-y 设z=2x+y，变量x，y满足条件x−4y≤−33x+5y≤25x≥1 设变量x,y满足条件:x+y=-1 y>=1,则目标函数z=4x+2y的最大值为 设z=2x+y式中变量x,y同时满足x-4y 设实数x，y满足条件x≥0x≤yx+2y≤3 设变量xy满足 x+y-3 x-y+1 3x-y+5 z=x+y/x 设变量xy满足条件x+y≤3,x-y≥-1,x≥0,y≥0.且目标函数z=2x+3y的最大值为a, 设z=x-y，式中变量x和y满足条件x+y-3≥0x-2y≥0，则z的最小值为___． 设变量x,y满足约束条件x-y>=-1,x+y>=1,3x-y 设变量x，y满足约束条件x−y≥0x+y≤1x+2y≥1 设变量x,y满足约束条件2x+y≤2,x≥y,y≥-1,则z=-y+3x的最大值为?