Solve the following problem manually using the B&B algorithm. You can use the computer to solve the individual problems generated. Create a branch-and-bound tree to display the steps you complete.

MAX: 6X1 + 8X2
Subject to: 6X1 + 3X2 ≤ 18
2X1 + 3X2 ≤ 9
X1, X2 ≤ 0
X1, X2 must be integers