Brahmagupta's Formula For Quadrilateral Area

Question: What is the area of a quadrilateral with sides equal to 18, 22, 39, and 41 respectively?

Answer: 798

console.log("********************************");
function Brahmagupta(a,b,c,d){
var perimeter=a+b+c+d;
var s = perimeter/2;
return Math.sqrt((s-a)*(s-b)*(s-c)*(s-d));
}
console.log(Brahmagupta(18,22,39,41));