The maximal area obtainable if we assume that the
farmer builds a field in the shape of an isosceles triangle, where the two
equal sides are the fenced sides, and the third side is the river is determined
using the same formula used in getting the area of an isosceles triangle.
THE FORMULA
Multiply the base
(length of the side of the river) and the height of the triable at its tallest
point, then divide the product in half.
A = 1/2 x b x h, where b is the base, and h is the height.
Plug your values
into the formula to find the area.
