S R
b. Pre-activity 2. Finding the sum of the exterior angles of a convex polygon by
completing the given equations based on the given illustrations.
1. Given: A RED with the given
measure of its interior angles.
Find the sum of its exterior angles
80°
by completing the given equations.
if m_DRE = 80, then mZSRD =
60°
if mZRDE = 600, then m BDE =
if mZRED = 400, then mZREP =
400
B
E E
therefore, the sum of the measures of the exterior angles of a triangle is:
mZSRD + MzBDE + m2REP =​