Question

problem 12: (first taught in lesson 23)
from this given statement, select the definition, property, postulate, or theorem that justifies the prove statement.
given: $overline{uw}paralleloverline{st}$
prove: $angle4congangle5$

Explanation:

When two parallel lines ($\overline{UW}\parallel\overline{ST}$) are cut by a transversal, alternate - interior angles are congruent. $\angle4$ and $\angle5$ are alternate - interior angles formed by the parallel lines $\overline{UW}$ and $\overline{ST}$ and a transversal, so the Alternate - Interior Angles Theorem justifies $\angle4\cong\angle5$.

Answer:

The Alternate - Interior Angles Theorem