An equilateral triangle is a triangle in which all three sides and angles are equal. All three internal angles of equilateral triangle measures 60 degree.
- If we know the length of each sides of equilateral triangle, then we can use below mentioned formula to calculate area of equilateral triangle.
Area of Equilateral Triangle = (sqrt(3)/4) * a * a
- If we know the length of altitude of equilateral triangle along with the length of side, then we can use below mentioned formula to calculate it’s area.
Area of Equilateral Triangle = (1/2) x Side x Altitude
Perimeter of Equilateral Triangle :
Perimeter of Equilateral Triangle : 3 X a
How does the area formula work?
Let us take a look at below diagram. We know are of a triangle is 1/2 * base * height. The value of h is sqrt(a2 – (a/2)2) = sqrt(3) * a / 2. So the area becomes 1/2 * a * (sqrt(3) * a / 2) = (sqrt(3)/4) * a * a
Examples:
Input : side = 4 Output : Area of Equilateral Triangle: 6.9282 Perimeter of Equilateral Triangle: 12 Input : side = 12 Output : Area of Equilateral Triangle: 62.3538 Perimeter of Equilateral Triangle: 36
C++
// CPP program to find area // and perimeter of equilateral triangle #include <bits/stdc++.h> using namespace std; // Function to calculate Area // of equilateral triangle float area_equi_triangle( float side) { return sqrt (3) / 4 * side * side; } // Function to calculate Perimeter // of equilateral triangle float peri_equi_triangle( float side) { return 3 * side; } // Driver Code int main() { float side = 4; cout << "Area of Equilateral Triangle: " << area_equi_triangle(side) << endl; cout << "Perimeter of Equilateral Triangle: " << peri_equi_triangle(side); return 0; } |
Java
// Java Program to find area and // perimeter of equilateral triangle import java.io.*; class GFG { // Function to calculate // Area of equilateral triangle static float area_equi_triangle( float side) { return ( float )(((Math.sqrt( 3 )) / 4 ) * side * side); } // Function to calculate // Perimeter of equilateral // triangle static float peri_equi_triangle( float side) { return 3 * side; } // Driver Code public static void main(String arg[]) { float side = 4 ; System.out.print( "Area of Equilateral Triangle:" ); System.out.println(area_equi_triangle(side)); System.out.print( "Perimeter of Equilateral Triangle:" ); System.out.println(peri_equi_triangle(side)); } } // This code is contributed // by Anant Agarwal. |
Python
# Python3 program to calculate Area and # Perimeter of equilateral Triangle # Importing Math library for sqrt from math import * # Function to calculate Area # of equilateral triangle def area_equilateral( side ): area = (sqrt( 3 ) / 4 ) * side * side print ( "Area of Equilateral Triangle: % f" % area) # Function to calculate Perimeter # of equilateral triangle def perimeter( side ): perimeter = 3 * side print ( "Perimeter of Equilateral Triangle: % f" % perimeter) # Driver code side = 4 area_equilateral( side ) perimeter( side ) |
C#
// C# Program to find area and // perimeter of equilateral triangle using System; class GFG { // Function to calculate // Area of equilateral triangle static float area_equi_triangle( float side) { return ( float )(((Math.Sqrt(3)) / 4) * side * side); } // Function to calculate // Perimeter of equilateral // triangle static float peri_equi_triangle( float side) { return 3 * side; } // Driver Code public static void Main() { float side = 4; Console.Write( "Area of Equilateral Triangle:" ); Console.WriteLine(area_equi_triangle(side)); Console.Write( "Perimeter of Equilateral Triangle:" ); Console.WriteLine(peri_equi_triangle(side)); } } // This code is contributed // by vt_m. |
PHP
<?php // PHP program to find area // and perimeter of equilateral triangle // Function to calculate Area // of equilateral triangle function area_equi_triangle( $side ) { return sqrt(3) / 4 * $side * $side ; } // Function to calculate Perimeter // of equilateral triangle function peri_equi_triangle( $side ) { return 3 * $side ; } // Driver Code $side = 4; echo ( "Area of Equilateral Triangle: " ); echo (area_equi_triangle( $side )); echo ( "\n" ); echo ( "Perimeter of Equilateral Triangle: " ); echo ( peri_equi_triangle( $side )); // This code is contributed // by vt_m. ?> |
Javascript
<script> //Javascript program to find area // and perimeter of equilateral triangle // Function to calculate // Area of equilateral triangle function area_equi_triangle(side) { return (((Math.sqrt(3)) / 4) * side * side).toFixed(4); } // Function to calculate // Perimeter of equilateral // triangle function peri_equi_triangle(side) { return 3 * side; } //Driver code var side = 4; document.write( "Area of Equilateral Triangle:" ); document.write(area_equi_triangle(side)+ "\n" ); document.write( "Perimeter of Equilateral Triangle:" ); document.write(peri_equi_triangle(side)+ "\n" ); //This code is contributed by shruti456rawal </script> |
Area of Equilateral Triangle: 6.9282 Perimeter of Equilateral Triangle: 12
Time Complexity: O(1)
Auxiliary Space: O(1)
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