Which of the following triangles has all three sides of equal length?

The triangle characterized by having all three sides of equal length is known as an equilateral triangle. This unique attribute ensures that not only are the sides equal, but the angles opposite those sides are also equal, each measuring 60 degrees. This property creates a highly symmetrical shape, making equilateral triangles particularly significant in various fields, including art, architecture, and mathematics.

In contrast, an isosceles triangle has only two sides that are of equal length, while a scalene triangle has all sides of different lengths. A right triangle is defined by having one angle that measures exactly 90 degrees and does not have any requirements regarding the lengths of the sides in relation to each other, meaning its sides can be equal or different. Thus, equilateral triangles stand out for their specific property of equal-length sides.