Polygons
Classification, interior and exterior angles, diagonals, regular polygons and area
The Polygons unit belongs to the Geometry and trigonometry section of Math Mental and has 15 lessons: classification, interior and exterior angles, diagonals, regular polygons and area.
Lessons in this unit
- Name from the number of sides
- Sides from the name
- Name from the angle sum
- Sum of the interior angles
- Angle of a regular polygon
- Sides from the angle sum
- Sum of the exterior angles
- Central angle of a regular polygon
- Practice: polygon angles
- Number of diagonals
- Sides from the diagonals
- Perimeter of a regular polygon
- Area from the apothem
- Review: diagonals, perimeter and area
- Polygon test
How to work through this unit
Follow the lesson order
The unit has 15 lessons of increasing difficulty. Finish one before moving on: the early techniques come back in the later questions.
Solve it before reading the solution
Work every question out on your own, then read the step by step and check the reason for each step instead of only comparing the final answer.
Lock it in during review
The question types you miss come back in practice and review until you get them right in a row. The unit test confirms the whole unit stuck.
Frequently asked questions about this unit
What does the Polygons unit cover?
Polygons belongs to the Geometry and trigonometry section and has 15 lessons: classification, interior and exterior angles, diagonals, regular polygons and area. The lessons start with the basic cases and build up to applications, always with a step-by-step solution.
What should I know before studying Polygons?
This page names the previous unit on the path. If it is not solid yet, go back and practice first; if there is no prerequisite, this is where the path begins.
How long does Polygons take?
Each lesson takes a few minutes. Most students do one or two a day and finish a unit in one or two weeks. The goal is answering correctly day after day, not clearing everything at once.
Are the Polygons exercises free?
Yes. Every Math Mental lesson is free and ad-free; you only need an account to save your progress.
Your first lesson takes five minutes
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