### Video Transcript

In the given figure, find the
measure of angle ππΆπ.

Observe that angle πΆπ΄π΅ is
vertically opposite angle ππ΄πΏ. This means that the two angles are
congruent. Similarly, angle π΄π΅πΆ is
vertically opposite and, therefore, congruent to angle ππ΅π. Since π΄π΅πΆ is a triangle, we know
that its internal angles sum to 180 degrees.

The internal angles of triangle
π΄π΅πΆ are angles πΆπ΄π΅, π΄π΅πΆ, and π΅πΆπ΄. Therefore, angle π΅πΆπ΄ has measure
180 minus 80 minus 30 equals 70 degrees. Finally, since angle ππΆπ is
vertically opposite angle π΅πΆπ΄, the two angles are congruent. Therefore, angle ππΆπ has measure
70 degrees.