TriArea

Calculate the area of a triangle given the vertices' coordinates and using the formula given.

A = 1/2*crossProduct(AB, AC)

Steps that must be taken to perform the task:

1. Determine vectors AB and AC.
2. Calculate cross product of vectors AB and AC.Calculation should be valid for a triangle in the x-y plane and for a triangle in space (x-y-z).
3. Determine the area of a triangle.