Answer:
The correct statement that describes how to determine the measure of angle 1 is:
The 81° angle and angle 2 are corresponding angles so angle 2 must measure 81°. Angles 1 and 2 are supplementary angles so angle 1 must measure 99°.
Step-by-step explanation:
- Corresponding angles are angles that occupy the same relative position at each intersection where a straight line crosses two others. In this case, the 81° angle and angle 2 are corresponding angles, so angle 2 must measure 81°.
- Supplementary angles are two angles whose measures add up to 180 degrees. Since angles 1 and 2 are supplementary angles, and angle 2 is 81°, angle 1 must measure 99° to make the total 180°.
Therefore, based on the properties of corresponding angles and supplementary angles, the correct measure of angle 1 is 99°.