What’s the pattern?

We are looking at the patterns involving the sum of the interior angles of a polygon.  We made a variety of polygons and measured the angles inside them.

We collected data in tables of values, and saw how that can be plotted using desmos.com (also there’s a free app)

We saw how the first differences of the table data is the same, and how that relates to the linear graph we saw.

There are two ways that we can calculate the sum of the interior angles.  We can multiply the number of sides by 180 then subtract 360.  We could also subtract two from the number of sides first, then multiply the result by 180.