Find the Area of Regular Polygon Given Radius

Learn how to find the area of a regular polygon when only given the radius of the the polygon. We go through an example involving a regular pentagon inscribed inside a circle with radius of 8 units. This problem involves using some trigonometry to find both the apothem and the side length of the polygon.

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[blonker]

Pov: Your math teacher gave your 2weeks worth of hw and you didn't understand anything he said

[noahcrook]

Geometry test today- these two minutes taught me the concept far better than an hour and a half of class time ever could. Thank you, my man!

[justaguy]

You taught me more in 3 minutes than me teacher in 1 hour. Thank you

[red-tippedmatches]

Thank you for teaching this in a way that is simple and straight forward. Doing school work during quarantine has been difficult, but your video helped clear this subject up for me.

[bencole]

Hi Mario! Geometry teacher here. If your students know the formula for the area of a triangle given 2 sides and an included angle (1/2 b*c*SinA), it's a huge shortcut in this method. You would no longer need to solve for the side length and apothem. Instead, you can treat the radius as both b and c, and the central angle as A. So you get 1/2 * (r^2)*Sin(360/n) * n.

[sarrankumarmohan]

Mr.Mario
Thank you so much for the regular uploads...
The way you teach the concepts is interesting...
Please upload for permutations and combinations too..

[grantdouglas]

Thank you for making it extremely clear and easy to understand. I like how you drew the triangle larger out to the side so that you could focus on it more. That really lets you solve one problem and then just plug it into the equation to find the area.

[mr.butterboi]

Crazy how much this is helping right now with homework, thanks a bunch

[Jamsome]

If only I had watched this before I took my test(which I failed), luckily I can do corrections for it so thanks to this I can hopefully pass.

[JesusMunoz-ikpq]

Nice vid i just start watching all geometry videos for my final!

[wishphobic]

Tysm!! This really helped me sm! I get so confused and geometry is one of my weak spots, so this helped a ton :)

[zeixtqz]

Very useful video, clear explanation and straight to the point.Thanks a lot.

[Itssjade]

Amazing teacher!!! I’ve been sitting here struggling trying to figure out one these problems on my homework so I went to YouTube and this video pops up, I followed your steps just with my work and I GOT ITTT!!❤

[LandoBassMan]

Ngl dude you helped me out soo much with my stress during math class. Thanks tons man

[vara.x]

I never understood these sin and cos and tan but thanks to u I learned all in 2 minutes

[daniel]

yo mr mario coming in clutch today thanks bb

[mathtutor]

Thank you Mario! Was just refreshing to teach to my students. Very, very helpful.

[Purepecha]

I love your videos just subbed and starting watching from your Algebra 1 videos

[evalutz]

thank you so much i was confused about using the radius to find the apothem

[xthomas]

Took me like a week of thinking to figure out the area of a regular polygon.