An equilateral triangle is a type of triangle. It is a regular polygon with unique properties: all three sides are equal in length, and all three angles in the corners are 60º.
Examples in real life can include traffic signs and tortilla chips.
You can remember the things that define an equilateral triangle because the name sounds like it has “equal” in it.
What are the three properties of an equilateral triangle?
Here are the three properties of an equilateral triangle:
- It is a regular polygon with three sides.
- All three sides are equal in length.
- All three angles are congruent and similar to 60º.
Remembering the properties of an equilateral triangle is very simple. There are three properties, which can help retain the properties since there is one for each corner or side of the triangle.
Finding the perimeter and area of equilateral triangles
Perimeter
Finding the perimeter of an equilateral triangle is easy. All sides are the same length, so all you must do is multiply the length of one side by three.
Area
To find the area of an equilateral triangle, you use the same formula as you would for any other triangle.
A triangle is half the size of a quadrilateral, so you have to halve the measurements you would use to find the quadrilateral area.
That formula is: ½ × base × height
What are the four types of triangles?
The four types of triangles are:
- equilateral;
- scalene;
- isosceles;
- right-angled.
