Hi,
I need to do this for some homework and I don't really understand... could anyone help with the following question:
Find the area of the pentagon PQRST with vertices P = (1,1,1), Q = (5,−3,1), R = (9, −1, −5), S = (2, 6, −5), T = (1, 2, 0). Hint: divide the pentagon into triangles...