Given: 2 || m; 21 * 23 Prove: p || Complete the missing parts of the paragraph proof. р 9 We know that angle 1 is congruent to angle 3 and that line I is parallel to line m because . We see that is congruent to by the alternate interior angles theorem. Therefore, angle 1 is congruent to angle 2 by the transitive property. So, we can conclude that lines p and q are parallel by the 1 2 m 3