It's because we may use the x4 in the last row as a Basic Variable, x4 will have a role like a slack variable. Therefore, we only need 3 artificial variables for the first three rows, because those rows do not have any variable that may be readily used as a Basic Variable.
5:45 and why we choose x3 instead of x5 as entering variable. both has the positive coefficient of 1
Hello! Yes, you are correct. In this case you may also choose x5 as the entering variable.
Thanks dude, your previous video and this one actually cleared my doubts.
You're welcome! I'm glad that the videos are helpful.
11:06 and here in the bottom table x6 should be the basic variable with the value of 1/2, not x4. bc x6 has entered and x4 left
You're correct again, thanks!
4:20 how do we know we have 3 artificial variables in this problem
It's because we may use the x4 in the last row as a Basic Variable, x4 will have a role like a slack variable.
Therefore, we only need 3 artificial variables for the first three rows, because those rows do not have any variable that may be readily used as a Basic Variable.