Area of Triangles · Superchallenge problem

Triangle $ABC$ has an area of $10$ square cm. Side $AB$ is extended past $B$ to a point $D$ so that $BD = AB$. Side $BC$ is extended past $C$ to a point $E$ so that $CE$ is twice as long as $BC$. What is the area of the four-sided shape $ACED$, in square centimeters?