-已知xy满足x+2y-5≤0 ,x≥0,x+2y-3≥0三个不等式 t=y/x的最大值：z等于根号下（x^2+y^2)的最小值u=(x-6)^2+(y-2)^2的最小值

已知正整数x,y满足：xy-x-y=0,则x+2y的最小值 已知正数x,y满足2x+8y-xy=0,x+y的最小值 已知未知数xy满足x^2+y^2+2x-4y+5=0,求xy的值 已知实数x,y满足2x-y≥0 x≤1 x+y+1≥0 则z=x^2-2xy+y^2已知实数x,y满足2x-y≥0 x≤1 x+y+1≥0 则z=x^2-2xy+y^2 的最大值 已知实数xy满足不等式组x≥0,y≤x,x+y-4≤0,则z=2x-y的最大值为 已知实数xy满足x²﹢y²-xy+2x-y+1=0求xy 已知实数xy满足x+2y 已知实数xy满足 x+y-2 已知实数x,y满足x²+y²-xy+2x-y+1=0 求x y 已知正实数x y满足x-根号xy-2y=0求 x+3根号xy+2y/2x-2根号下xy-y 已知实数xy,满足10x²-2xy+y²+6x+1=0,求x+y 已知xy满足条件 0≤x≤4,0≤y≤3,x+2y≤8,则z=2x+5y的最大值 已知实数x,y满足三个式子 x-y-2≤0 x+2y-5≥0 y-2≤0 则z=x^2+y^2/xy的取值范围? 已知实数x、y满足2x2-7xy+3y2=0,求x：y 已知实数x满足x^2+2xy+y^2-(x+y)-6=0则x+y的值 已知xy满足约束条件x+2y-4≤0 x-y-1≤0 x+2≥0求目标函数z=x+2y+2的最大值已知xy满足约束条件x+2y-4≤0 x-y-1≤0 x+2≥0求目标函数z=x+2y+2的最大值和最小值 已知实数x、y满足xy>0,且8/xy+1/x+1/y=1, 已知x、y满足(x+1)^2+|y-2|=0,求代数式 2xy X 5x^2y+(1/2x^2y^2-3y) X 2x+6xy的值