This lesson teaches how to find angle measurements using vertical angles. It begins with a review of supplementary angles, explaining that they sum to 180 degrees and can be adjacent. When two lines intersect, they form adjacent supplementary angles. The lesson demonstrates calculating angle measurements by subtracting known values and highlights that vertical angles are congruent. It concludes with solving problems involving vertical angles, emphasizing their congruence and how to determine unknown angle measurements.

What is the significance of adjacent supplementary angles when two lines intersect?

How can you find the measure of angle EBD if angle ABC is 115 degrees?