The areas of triangle BMP and CMB are equal because the base and height are the same. Therefore, <em>A</em>BMP=<em>A</em>CMB=21m^2 which is due to transitivity.
The ratio of the areas of triangles ACP to PCB is the same as their bases AP and BP which is 1:3. This is due to area of triangles.
After that, we use Substitution and Algebra to calculate the area of: <em>A</em>ACP=
Finally, we add all of the areas together. (Or you could've just multiplied in the last equation by 4 rather than 3 to get the <em>A</em>ABC sooner.) <em>A</em>ABC=<em>A</em>ACP+<em>A</em>PCB=14+42=56m^2