3 Answers: B, C, D
Essentially, everything but choice A is true.
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Explanation:
Let's go through the answer choices one by one
- Choice A is false because angles 3 and 2 are not alternate interior angles. Instead, they are vertical angles.
- Choice B is true because angle 1 and angle 3 form a straight line.
- Choice C is true. Alternate interior angles are angles that are inside the parallel lines, and are on alternating sides of the transversal cut. The other pair of alternate interior angles is angle 4 and angle 5.
- Choice D is true. We go from [tex]m \angle 1 + m \angle 3 = 180[/tex] to [tex]m \angle 1 + m \angle 6 = 180[/tex] after replacing angle 3 with angle 6. Such a replacement can be made because angle 3 and angle 6 are the same measure.
