Answer 1

#include <iostream>
#include <cmath>
using namespace std;

int main (){
float s1,s2,s3,s,p,area;

cout <<"Enter side 1: ";cin>>s1;
cout <<"Enter side 2: ";cin>>s2;
cout <<"Enter side 3: ";cin>>s3;

s = (s1+s2+s3)/3;
p=(s-s1)*(s-s2)*(s-s3);
area=sqrt (p);
cout <<"Area of triangle = "<<area;
}