Question

Which properties belong to all isosceles triangles? Check all that apply.

Answer 1

3 Answers:  Choice A, Choice C, Choice E

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Explanation:

Let's go through the answer choices to see which are true and which are false.

• A) True. The base angles are the same measure, and they are opposite the congruent sides. Any isosceles triangle has exactly two congruent sides.
• B) False. This is describing an equilateral triangle (where all three angles are 60 degrees each).
• C) True. See choice A.
• D) False. This is describing an equilateral triangle where all sides are the same length.
• E) True. You can use the SAS (side angle side) congruence theorem to prove that the angle bisector is also the perpendicular bisector. Furthermore, this segment is also a median. This only applies to the vertex angle.