The complete flow proof is:
- <em />
<em> ---- Given</em> - <em> </em>
<em> ---- Given</em> - <em />
<em> ----- </em>
<em> and </em>
<em> are supplementary angles</em> - <em />
<em> ----- </em>
<em> and </em>
<em> are same-side interior angles</em> - <em />
<em> ----- Proved</em>
We have:


<u>The proof of </u>
<u> is as follows:</u>
The first statement is:
---- Given
The next statement is:
---- Given
Supplementary angles add up to
.
So, the third statement is:
-----
and
are supplementary angles
Same side of interior angles add up to
.
So, the fourth statement is:
-----
and
are same-side interior angles
Because the angles are supplementary angles and also same-side interior angles, then it means that <em>line a is parallel to line b</em>
So, the last statement is:
----- Proved
Read more about proofs of parallel lines at:
brainly.com/question/18396272