If you are unfamiliar with Heron's Formula, the "s" means semi-perimeter, which is one half of the triangle perimeter.
perimeter = 12 + 14 + 16 = 42
semi-perimeter = 21
Area = Square Root (21 * (21-12)*(21-14)*(21-16))
Area = Square Root (21 * 9 * 7 * 5)
Area = Square Root (6,615)
Area = 81.33
