which lines (if any) can be proved parallel? By which theorem?

Given that <1 and <5 are congruent, which lines can be proven parallel

Without knowing the specific angles and lines, it is impossible to determine which lines can be proven parallel or which theorem would be applicable. You need to provide more information about the specific lines and angles involved in order to make a determination.

To determine which lines, if any, can be proved parallel, we need to examine the given information, specifically the congruence of angles <1 and <5.

To prove two lines are parallel, we generally use one of two theorems: the Alternate Interior Angles Theorem or the Corresponding Angles Theorem.

1. Alternate Interior Angles Theorem: If alternate interior angles formed by a transversal cutting two lines are congruent, then the lines are parallel.

2. Corresponding Angles Theorem: If the corresponding angles formed by a transversal cutting two lines are congruent, then the lines are parallel.

Based on the given information that <1 and <5 are congruent, we can conclude that the lines associated with these angles could be proven parallel using the Corresponding Angles Theorem.

However, we cannot determine which specific lines are parallel without additional information about the configuration of the lines and angles.

To determine which lines (if any) can be proven parallel when <1 and <5 are congruent, we need more information about the figure or diagram you are referring to. The congruence of angles <1 and <5 does not provide enough information on its own to prove parallelism between lines.

To establish parallelism between lines, we typically rely on the following theorems:

1. Corresponding Angles Postulate: If a transversal intersects two parallel lines, then the corresponding angles formed are congruent.

2. Alternate Interior Angles Theorem: If a transversal intersects two parallel lines, then the alternate interior angles formed are congruent.

Without further details or a diagram, it is not possible to determine which lines, if any, will be proven parallel using the given information.