public double Area() //площадь
{
double p = this.Perimetr() / 2;
double ar = Math.Sqrt(p * (p - Edge.lengthEdge(c, d)) * (p - Edge.lengthEdge(c, e)) * (p - Edge.lengthEdge(d, e)));
return(ar);
}
public double Perimetr() //периметр
{
double perim = Edge.lengthEdge(c, d) + Edge.lengthEdge(c, e) + Edge.lengthEdge(d, e);
return(perim);
}