On Geogebra, use the algorithm from the lesson to draw a star that is created from three overlapping $5-$pointed stars. To do this, you will need to determine which number to add repeatedly mod $15$ to get this design. As with the last activity, start by using the regular polygon tool to make a regular $15$ sided polygon. Change the labels on the points on the vertices to be the numbers $0-14$ and use the hide tool to hide the polygon and its edges so that only the points can be seen. Make your star on these points, export it as a picture, and paste it into your homework document. Tell which number or numbers could be added repeatedly mod $15$ to make the star.