54.4k views
1 vote
Lines b and c are parallel

Which pairs of angles are supplementary? Select all that apply

Lines b and c are parallel Which pairs of angles are supplementary? Select all that-example-1
User Navule
by
4.4k points

2 Answers

4 votes

Answer:

The supplementary angles are angles 2 and 4 for being adjacent and angles 3 and 5 for being internal conjugate angles.

Explanation:

Supplementary angles are those that when added measure 180 degrees, that is, form a flat angle.

Alternate angles are a set of non-adjacent angles (adjacent angles are those that have the vertex and a common side while the other two sides are opposite semi-straight) on both sides of a transverse line. This intercepts two lines (generally parallel) forming eight angles that can be classified as external alternates or internal alternates.

The alternate external angles are those that are on the outside of the parallels on different sides of them and on different sides of the transversal. In the case of the figure, angles 1 and 8 are alternate external, as are angles 2 and 7. These pairs of angles are congruent, that is, equal.

On the other hand, the internal alternate angles are those between the parallels on different sides of them and on different sides of the transversal. In this case, angles 3 and 6 are internal alternates, as are angles 4 and 5. These angles are also congruent, that is, equal.

The internal conjugate angles are those internal angles to the two parallel lines and on the same side of the transverse. In this case, the internal conjugate angles are angles 3 and 5, as well as 4 and 6.

On the other hand, the external conjugate angles are those angles external to the two parallel lines and on the same side of the transversal. In this case these are angles 1 and 7 and angles 2 and 8.

Unlike the alternate angles, which are equal, the internal and external conjugate angles are supplementary.

Finally, two angles are adjacent if they have one side, the vertex in common and are supplementary. Adjacent angles in this case are angles 2 and 4.

Finally, of the options given, the supplementary angles are angles 2 and 4 for being adjacent and angles 3 and 5 for being internal conjugate angles.

User William Holroyd
by
5.5k points
4 votes

Angles 2 and 4, and Angles 3 and 5 are supplementary. Supplementary means two angles add up to 180 degrees (aka a straight line).

User Glennys
by
4.5k points