By A Mystery Man Writer
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.
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Angles in a Pentagon - Maths with Mum
All About Pentagons - DoodleLearning
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Spotlight on Math: The Pentagon Problem — Presidio Knolls School
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The maximum number of right angles in a polygon - Math Central
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