Basic Mathematics
# Length and Area

$ACDE$ is a rectangle and $B$ is a point on side $AC$ such that $\triangle BED$ is an equilateral triangle with side length $36,$ what is the area of the shaded region in the above diagram?

If

$8$, what is the area of the octagon?

If the side length of a regular octagon is$6$, what is the area of the hexagon?

If the side length of a regular hexagon is$3$ and outer radius $8?$

What is the area of an annulus with inner radius