Calculate the area of the equilateral triangle by using the formula specifying the length of one side.
When the length of one side is input and "Calculate the area of a triangle" button is clicked, the area, the perimeter, and the height of the equilateral triangle are calculated and displayed.
![Equilateral triangle](/img/area_en/equilateral_triangle.png)
![Formula of area of equilateral triangle](/img/area_en/equilateral_triangle1.jpg)
![Formula of perimeter of equilateral triangle](/img/area_en/equilateral_triangle2.jpg)
![Formula of height of equilateral triangle](/img/area_en/equilateral_triangle3.jpg)
Area, perimeter, and height of equilateral triangle whose length of one side a is 1
Area S: 0.43301270189222
Perimeter L: 3
Height h: 0.86602540378444
Perimeter L: 3
Height h: 0.86602540378444