A (not necessarily convex) 11-sided polygon can have at most how many right interior angles? Be sure to explain why an 11-sided polygon can have that number of right interior angles, and why it can’t have any more than that. Please help!
The sum of external angles of any polygon is 360 degrees. Having a right angle contributes 90 degrees to the external angles, so there can only be a maximum of 3 right angles. (If there were 4, there wouldn't be room for any more angles.)