Question 1059176
1.  Reason:  Given
2.  Reason:  Since line m and line n are parallel, corresponding angles are congruent
3.  Reason:  Congruent angles have equal measure
4.  Reason:  A linear pair is formed when two straight lines intersect.
5.  Reason:  Linear pairs of angles are supplementary.
6.  Reason:  Supplementary angles add to 180 degrees.
7.  Statement:  m_angle3 + m_angle1 = 180 degrees   Reason: Substitution (statement #6 and statement #3)
8.  Statement:  angle3 is supplementary to angle1      Reason:  angles that add to 180 degrees are supplementary