Question

which figure has exactly three lines of symmetry?
right triangle
square
equilateral triangle
regular pentagon

Explanation:

Step1: Recall line - symmetry rules

A right - triangle has at most 1 line of symmetry. A square has 4 lines of symmetry. An equilateral triangle has 3 lines of symmetry. A regular pentagon has 5 lines of symmetry.

Answer:

equilateral triangle