Question

How to calculate the area of a pentagon in C++

Answer 1

#include <iostream>

float pentagon_area(float side, float apothem) {
    return 5.0f * (side * apothem) / 2.0f;
}

int main() {
    float side = 5.0f;
    float apothem = 3.0f;

    float area = pentagon_area(side, apothem);

    std::cout << "Area = " << area << std::endl;
}



/*
run:

Area = 37.50

*/

 

70+ SQL courses for beginners and professionals

Answer 2

#include <iostream>
#include <cmath>

double area_regular_pentagon(double side) {
    return (1.0 / 4.0) * std::sqrt(5.0 * (5.0 + 2.0 * std::sqrt(5.0))) * std::pow(side, 2);
}

int main() {
    std::cout << area_regular_pentagon(7.0) << std::endl;
}


/*
run:

84.3034

*/

 

70+ SQL courses for beginners and professionals