Diagonals in Polygons

Use the segment tool (first click on the line icon [icon]/images/ggb/toolbar/mode_join.png[/icon], then the segment icon [icon]/images/ggb/toolbar/mode_segment.png[/icon]) to draw the maximum number of triangles you can, inside the polygons. Only use the polygon’s vertices as points, such that no 2 diagonals overlap.
In your notebook record the number of triangles made inside each polygon. Create a chart like this one to help you.[br]
How does this second table relate to the first one? What connections can be made?
What is the sum of interior angles of a polygon with 9 sides? Explain your thinking.
Come up with a formula in the form of [math]S\left(n\right)=[/math] , where S is the sum of interior angles and n is the number of sides. Using your work with the diagonals and the table, explain why it works.
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