Question

classify this triangle by its sides.
equilateral
isosceles but not equilateral
scalene

Explanation:

Step1: Recall triangle classification by sides

A triangle is equilateral if all three sides are equal (and all angles \(60^\circ\)). An isosceles triangle has at least two equal sides (and at least two equal angles). A scalene triangle has all three sides of different lengths (and all angles different).

Step2: Analyze the given triangle

The triangle has two marked equal angles (the small arcs). By the Isosceles Triangle Theorem, sides opposite equal angles are equal. So, two sides are equal, but not all three (since not all angles are marked equal, implying it's not equilateral). Thus, it's isosceles but not equilateral.

Answer:

B. isosceles but not equilateral (assuming the options are labeled as A: equilateral, B: isosceles but not equilateral, C: scalene; if the original options have no labels, adjust based on the order: the middle option "isosceles but not equilateral" is correct)