+9665 3 ways.
1) Let b denote the base of the triangle and h denote the height of the triangle.
Area = \(\dfrac{bh}{2}\)
2) Let a, b, c denote the 3 sides of the triangle respectively and s = \(\dfrac{\text{Perimeter}}{2}\)
Area = \(\sqrt{s(s-a)(s-b)(s-c)}\)
3) Let a and b denote any 2 sides of the triangle and \(\theta\) denote the angle included in the 2 sides.
Area = \(\dfrac{ab\sin \theta}{2}\)
Where \(\sin x = \dfrac{e^{ix}-e^{-ix}}{2i}\)
Where \(e^x = 1 + x + \dfrac{x^2}{2}+\dfrac{x^3}{2\times 3}+\dfrac{x^4}{2\times 3\times 4}+......\)
and \(i = \sqrt{-1}\)
