Question

which triangle is equilateral?

Explanation:

Step1: Recall equilateral - triangle definition

An equilateral triangle has all three sides of equal length and all three angles equal to 60°. Visually, it has a symmetrical shape.

Step2: Examine each triangle

The first triangle is a right - triangle, not equilateral. The second triangle has unequal side lengths. The third triangle has a symmetrical shape with all sides likely equal, which is characteristic of an equilateral triangle. The fourth triangle is an isosceles triangle with two equal sides but not all three equal.

Answer:

The third triangle (from the top - left, going row - by - row) is equilateral.