Question

Complete the two-column proof found in the attachment

Answer 1

1) m<1+m<2=180 ========> supplementary angles
2) m<3+m<2=180 ========> opposite angles are equal (vertical angles
                                                  theorem)
3) m<3 and m<5 are supplementary ====> Consecutive Interior Angles 
4) L || M =====> corresponding angles converse.(If two lines cut by a
                            transversal so that corresponding angles are
                            congruent,then the lines are parallel to each other.)