It can easily be shown that triangles ADO and CBO are similar with a 2:1 ratio, using an angle-angle-angle argument. Therefore, .
Triangle AOB has a "base" of 2 and a height equal to AD, or 8 (since BDA is a right angle). Hence,
Hello, Telo!
Trapezoid
Find the area of the shaded portion.
Code:B 4 C .* - - - * .*:| * * .*:::| * * .*::::*|O * .*:::* 6| * .*::* | * .*:* | * ** |* A * - - - - - - - * D 8
Since
Refering to the areas of the triangles:
. .
. .
Therefore: .