Example 3
In the following diagram, and . If , , and , find the measures of the unknown angles and the values of and .
- Find the relationship between two angles that have the same variable.
- Use the Same-Side Interior Angles Theorem.
- Use substitution and solve for .
- Find and using substitution.
- Find the relationship between one of the known angles and the last unknown angle, .
- Use the Alternate Interior Angles Theorem.
- Use the definition of congruence and substitution to find .
- Use substitution to solve for .