I am attempting to make a model of an iris diaphragm however I do not know how to rotate polygon objects

Here is a link to the graph: Polar coordinates
I would appreciate help.

Looks like you have the framework needed! Try adjusting the c variable to have minimum and maximum values of 0 and 2pi, respectively. Some other adjusting will be needed to fix a rogue triangle, but moving the c slider will rotate the triangles!

But how do I move the center of rotation so that it is in the center of each triangle?

See if this helps. You’ll just need to define the center of your polygon(s) and then you can use this idea. Let me know if you need any clarification on anything! Graphing Calculator