Problem #DES-150325

Problem

Today we will be finding the areas of some geometric figures. Here is a brief reminder of how to calculate the area of common shapes.

In the picture below, the area of the rectangle is $|AB|\times |AD|$.

The area of a triangle is given by $\frac{1}{2}bh$, where $b$ is the length of a chosen base and $h$ is the height. In this case, the segment $AB$ is the base and $CD$ is the altitude corresponding to the base $AB$.

The area of a circle with radius $r$ is $\pi r^2$. The number $\pi$ is approximately 3.14159 to five decimal points.