Given an integer d which is the length of the diagonal of a pentagon, the task is to find the area of that pentagon.
Examples:
Input: d = 5
Output: 16.4291
Input: d = 10
Output: 65.7164
Approach: Pentagon is a regular polygon having five equal sides and all equal angles. The interior angles of pentagon are of 108 degrees each and the sum of all angles of a pentagon is 540 degrees. If d is the diagonal of the pentagon then it’s area is given by:
Below is the implementation of the above approach:
C++
// C++ program to find the area of // Pentagon with given diagonal #include <bits/stdc++.h> using namespace std; // Function to return the area of the // pentagon with diagonal d float pentagonArea( float d) { float area; // Formula to find area area = (d * d * (-5 + sqrt (45)) * sqrt ( sqrt (20) + 5)) / 8; return area; } // Driver code int main() { float d = 5; cout << pentagonArea(d); return 0; } |
Java
// Java program to find the area of // Pentagon with given diagonal import java.text.*; class GFG{ // Function to return the area of the // pentagon with diagonal d static double pentagonArea( double d) { double area; // Formula to find area area = (d * d * (- 5 + Math.sqrt( 45 )) * Math.sqrt(Math.sqrt( 20 ) + 5 )) / 8 ; return area; } // Driver code public static void main(String[] args) { double d = 5 ; DecimalFormat dec = new DecimalFormat( "#0.0000" ); System.out.println(dec.format(pentagonArea(d))); } } // This code is contributed by mits |
Python3
# Python3 program to find the area of # Pentagon with given diagonal # from math lib import sqrt() method from math import sqrt # Function to return the area of the # pentagon with diagonal d def pentagonArea(d) : # Formula to find area area = (d * d * ( - 5 + sqrt( 45 )) * sqrt(sqrt( 20 ) + 5 )) / 8 return round (area , 4 ) # Driver code if __name__ = = "__main__" : d = 5 print (pentagonArea(d)) # This code is contributed by Ryuga |
C#
// C# program to find the area of // Pentagon with given diagonal using System; class GFG{ // Function to return the area of the // pentagon with diagonal d static double pentagonArea( double d) { double area; // Formula to find area area = (d * d * (-5 + Math.Sqrt(45)) * Math.Sqrt(Math.Sqrt(20) + 5)) / 8; return area; } // Driver code public static void Main() { double d = 5; Console.WriteLine( "{0:F4}" ,pentagonArea(d)); } } // This code is contributed by mits |
PHP
<?php // PHP program to find the area of // Pentagon with given diagonal // Function to return the area of the // pentagon with diagonal d Function pentagonArea( $d ) { $area ; // Formula to find area $area = ( $d * $d * (-5 +sqrt(45)) * sqrt(sqrt(20) + 5)) / 8; return $area ; } // Driver code { $d = 5; echo (pentagonArea( $d )); return 0; } //This code is contributed by Mukul singh. |
Javascript
<script> // javascript program to find the area of // Pentagon with given diagonal // Function to return the area of the // pentagon with diagonal d function pentagonArea( d) { let area; // Formula to find area area = (d * d * (-5 + Math.sqrt(45)) * Math.sqrt(Math.sqrt(20) + 5)) / 8; return area; } // Driver code let d = 5; document.write(pentagonArea(d).toFixed(4)); // This code is contributed by gauravrajput1 </script> |
16.4291
Time Complexity: O(1)
Auxiliary Space: O(1)
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