Recall what you learned about angle relationships in previous courses. (See the Math Notes box in this lesson if you need a reminder.) Determine the measures of the labeled angles. The double arrowheads indicate that the pair of lines is parallel. Homework Help ✎
All three of these can be solved using multiple techniques related to parallel lines.
: Corresponding angle with , so .
: and are vertical angles, so they have equal measures. Therefore, .
: and form a pair of supplementary angles, so . and form a pair of supplementary angles. How are and related?
Since there are parallel lines, look for relationships between pairs of angles such as alternate interior, corresponding, or same-side interior.