Heron's Formula

an adventure for GCSE-man

The derivation of this interesting result follows in several steps, each of which is within the scope of GCSE-man.

Step 1: the trigonometrical equivalent of Pythagoras' Theorem

Step 2: GCSE-man triangle trigonometry

Step 3: Combining the formulae

Step 4: GCSE-man algebra

Step 5: Putting it all together

Step 6: Looking at it from a different point of view

Step 7: An extension

This page was set up by Peter Mitchell on 19th July, 2000;slightly revised 28th January, 2006.