∠BEG and ∠BEA both share the common side B and the common corner E. That means they are adjacent angles. Together, they create a big angle, ∠AEG. To find the angle measurement of ∠AEG, you can just add up the measurements of the two adjacent angles, ∠BEG and ∠BEA:
54° + 27° = 81°.
That means ∠AEG = D) 81°.
