#include<stdio.h>
#include<math.h>
int main() {
int side;
float area, r_4;
r_4 = sqrt(3) / 4;
printf("\nEnter the Length of Side : ");
scanf("%d", &side);
area = r_4 * side * side;
printf("\nArea of Equilateral Triangle : %f", area);
return (0);
}
Output :
Enter the Length of Side : 5
Area of Equilateral Triangle : 10.82