An analyst came up with the following relationships for a problem in his company. Which relationships are valid for a linear program, and which are not? Explain why or why not for each.
Max 4x + 3 XY
s. t. 2x + Y<50
X-4Y >6
1.5 X2 + 6Y > 21
- X + Y = 5
5X +3underroot7 380
X, Y>0