9th grade math problem

Question

In triangle ABC, side AB and BC are congruent. What type of triangle is this? What two angles do you know are congruent?

Answer 1

Hi, Madison! If you have a triangle where 2 sides are congruent, the triangle is called an isosceles triangle.

The isosceles triangle theorem states that if two sides are congruent, then both of the opposite angles are also going to be congruent. In this case, since side AB and side BC are congruent, we can determine that the angle opposite of AB (angle C) and the angle opposite of BC (angle A) are congruent.

Hope this helps!