A Survey of Right Angles in Convex Pentagons

A regular pentagon, of course, has no right angles, but irregular pentagons can have one, two, or three (but not four, nor five). There are two varieties for both two and three right angles in pentagons -- the right angles can be consecutive, or non-consecutive.

Pentagon Shape - Definition, Properties, Pentagon Sides

right angle

Polyhedra, tessellations, and more.

7-fold

Solved (b) hexagon pentagon Π convex O concave has one or

The maximum number of right angles in a polygon - Math Central

Show that any convex pentagon and interior which has a pair

五角形 - Wikipedia

An equilateral pentagon with all sides of length 2 contains two