A composite figure has three congruent triangles removed from it what is the area of the shaded region?

Congruent triangles are triangles with the same sides and the same measure of angles. For instance you are given triangle DEF which is similar to triangle FGH. From the figure, side FH is larger than side DF. So the statement of them being congruent cancels out. Triangle DEF is smaller in size than triangle FGH. So they are not congruent. The slope is defined as the rise over run. Side DF has the same slope as side FH. Sides DE and FE are proportional to sides FG and HG.