Lines A and B are parallel based on the Converse of Alternate Angles theorem. By using this it shows the lines are parallel which is what we are trying to prove. <1 and <2 are congruent and they are also both Alternate Exterior angles. As they are are both on the exterior of the parallel lines. The parallel lines also have a transversal cutting through it. The picture is part of stair railings.
This is a picture of the Colosseum which is located in Rome, Italy. It was essentially a sports arena back when it was first built. <1 and <2 are interior alternate angles and are also both congruent. Lines A and B are congruent based on the Converse of Alternate Angles theorem. To prove that lines A and B are parallel we use the converse which is what we also did with <1 and <2. They are both interior angles because they are on the inside of the parallel lines. They also have a transversal running through it.
