已知实数X Y满足4X+Y-9>0 则X-3Y的最大值是多少?

已知实数x,y满足x-y 已知实数X,Y满足{|x+y| 已知实数x,y满足（x+y)(x+y+3)-4=0则x+y的值是 已知实数X Y满足4X+Y-9>0 则X-3Y的最大值是多少? 已知实数x、y满足-4 已知实数x,y满足-4 已知实数x,y满足{x=>0,y 已知实数x,y满足{x=>0,y 已知实数x、y满足x²+y²+4x-6y+13=0 已知实数xy满足 4x+y-9>=0 x-y-1 已知实数x,y满足：y 已知实数x,y满足条件x≥0,y≥x,3x+4y≤12,则(x+2y+3)/(x +1)的最大值是 已知:实数x、y满足x2+y2-4x-6y+13=0则y的x次方= 已知实数x.y满足3x+4y-15＝0,则x平方加y平方的最小值 已知实数x 、y满足|y-√3|+√x-4=0 则y的x次方等于 已知正实数x,y满足x+y+1/x+9/y=10,则x+y的最大值是 已知实数X,Y满足2X方-4XY+4Y方-6X+9=0则X倍根号下8Y= 已知实数x,y满足约束条件x+y>3,y