Question

if two line segments are congruent, which of the following must be true?
a. they have equal lengths.
b. they form a right angle.
c. they are equal.
d. they share an endpoint.

Explanation:

To determine the correct answer, we analyze the definition of congruent line segments. Congruent line segments are defined as having the same length.

• Option A: This aligns with the definition of congruent line segments (equal lengths).
• Option B: Forming a right angle is not a requirement for congruent segments; they can be in any orientation.
• Option C: The term "equal" is vague here, while "equal lengths" (Option A) is precise for congruent segments.
• Option D: Sharing an endpoint (being adjacent) is not necessary for congruence; they can be anywhere as long as their lengths are equal.

Answer:

A. They have equal lengths.