About This Lesson
Look for & use to determine all angles in each figure ...
• Vertical angles
• Parallel lines (use Parallel Theorem) … must be marked, DON’T ASSUME !
• Complementary angles (sum to 90o)
• Supplemental angles (sum to 180o)
• Isosceles triangles … angles opposite congruent sides in a triangle are congruent
• Equiangular triangles, or other regular polygons … all angles congruent
• Triangles (angles sum to 180 deg), quadrilaterals (angles sum to 360 deg), pentagons
(angles sum to 540 deg)
