Answer:
- alternate interior angles are congruent
- corresponding parts of congruent triangles are congruent
- definition of a parallelogram
Explanation:
Step Statement ⇒ Reason
1 RSTU is a parallelogram ⇒ Given
2 Side RS || Side TU and Side RU || Side TS ⇒ definition of a parallelogram
3 ∠RSU≅∠TUS and ∠RUS≅∠TSU ⇒ alternate interior angles are congruent
4 Side SU ≅ Side US ⇒ reflexive property
5 ΔRSU≅ΔTUS ⇒ ASA postulate
6 Side RS ≅ Side TU and Side RU ≅ Side TS ⇒ corresponding parts of congruent triangles are congruent