C Program to find the area of a pentagon

Program

#include<stdio.h>
void main()
{
	int apothem, side;
	float area, area_num;
	printf("Enter the apothem:\t");
	scanf("%d", &apothem);
	printf("Enter the length of side:\t");
	scanf("%d", &side);
	area_num = (5 * side * apothem);
	area = area_num / 2;
	printf("Area of pentagon: %f\n", area);
}

Output

Enter the apothem:	3
Enter the length of side:	5
Area of pentagon: 37.500000