The semicircle is not a polygon because the top of the half circle is curved.
No, the figure is not a polygon because the top of the half circle is curved.
![\"\"](\"http://www.mathskey.com/userfiles/image/steps_images/step1.JPG\")
![\"\"](\"http://www.mathskey.com/userfiles/image/steps_images/solution.JPG\")