Question

What are the reasons to #3 and #5??

options for both #3 and #5

- CPCTC
- Given
- When two lines are parallel and cut by a transversal, the consecutive interior angles are supplementary
- opposite sides of a parallelogram are parallel
- reflexive property
- angles that are supplementary to the same angle are congruent

Answer 1

Answers:

• 3) When two lines are parallel and cut by a transversal, the consecutive interior angles are supplementary.
• 5) angles that are supplementary to the same angle are congruent.

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Step-by-step explanation:

Basically, statements 3 and 4 are nearly identical. They both use the exact same reasoning. For statement 3, the parallel lines are QT and RS, with QR being the transversal. Refer to the same side interior angles theorem. It's also known as the consecutive interior angles theorem.

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For statement 5, consider the idea that if

Q+R = 180

Q+T = 180

then those two equations lead to T = R. Both angles T and R are supplementary to angle Q, so they must be the same angle. So that's why we go with the "angles that are supplementary to the same angle are congruent" option for this part.