Answer:
1.
,
: Given
2.
: If lines ||, corresponding
are =.
3.
: If lines ||, alternate interior
are =.
4.
: Substitution.
5.
: If two
of a triangle are =, sides opposite are =.
Step-by-step explanation:
We have been given a two column proof and we are asked to match the correct reason with each statement.
We have been given that line segment RS is parallel to line segment AB and measure of angle 1 is equal to measure of angle 2.
1.
,
: Given
We know corresponding angles of two parallel lines are equal, therefore, measure of angle B is equal to measure of angle 1.
2.
: If lines ||, corresponding
are =.
We know that alternate interior angles of two parallel lines are equal. We can see that angle A and angle 2 are alternate interior angles of parallel lines RS and AB, therefore, measure of angle A is equal to measure of angle 2.
3.
: If lines ||, alternate interior
are =.
We have been given that
. We figured that
and
. By substitution property of equality
.
4.
: Substitution.
We know that if two angles of a triangle are equal, then the sides opposite to these angles are also equal. We can see that side RA is opposite side of angle B and side RB is opposite side of angle A.
Since
, then side
.
5.
: If two
of a triangle are =, sides opposite are =.