They are regular polygons.
Equilateral triangle or any other type of a regular polygon.
An equilateral polygon is one in which all sides are congruent. The angles may or may not be congruent. The simplest example is an equilateral triangle which must also be equiangular and so is a regular polygon. A rhombus is an equilateral quadrangle. The rhombus, in general, is not regular - only the square (a special type of rhombus) is regular.
The answer is in your question it is defined to be a regular polygon as for example an equilateral triangle
An equilateral triangle is a polygon that has a measure of 60o for each angle.
A right angle triangle or an isosceles triangle.
a square
A type of polygon is a rhombusial polygon, trysectalnict polygon, and a equilateral polygon.
A triangle, a square, a rectangle, a pentagon are all polygons.
a equilateral triangle has all the sides the same length.
An equilateral triangle.
Equilateral triangle
Triangle