Phytagorean Theorem i think
B is the image of D, B is the image of E and C is the image of D
These are the only points where the image is to the left and down from the stated point.
Adjacent angles are angles that have a common side and a common vertex. The only one that fits this would be <FEC and <FEH because it shares the side of FE and common vertex of E. I hope this helps you. :)
