public static double area(Coordinate a,Coordinate b,Coordinate c){
  return Math.abs(((c.x - a.x) * (b.y - a.y) - (b.x - a.x) * (c.y - a.y)) / 2);
}

public static double area ( Coordinate a , Coordinate b , Coordinate c ) { return Math . abs ( ( ( c . x - a . x ) * ( b . y - a . y ) - ( b . x - a . x ) * ( c . y - a . y ) ) / 2 ) ; }
computes the 2d area of a triangle . the area value is always non - negative .
