Question

13 Prove that: If two lines are parallel to the same line, they will be parallel to each other.

Answer 1

Step-by-step explanation:

The first is if the corresponding angles, the angles that are on the same corner at each intersection, are equal, then the lines are parallel. The second is if the alternate interior angles, the angles that are on opposite sides of the transversal and inside the parallel lines, are equal, then the lines are parallel.

If two lines are cut by a transversal and the alternate exterior angles are equal, then the two lines are parallel. Angles can be equal or congruent; you can replace the word "equal" in both theorems with "congruent" without affecting the theorem. So if ∠B and ∠L are equal (or congruent), the lines are parallel.