How to find the Area of a pentagon

How to find the area of a regular pentagon with right triangle trigonometry.

[alexchristian]

Thank you so much I couldn’t find a video for doing it with a pentagon and you just did the exact same problem for me. My teacher still says the answer is wrong but that’s just her

[pantojafambam]

Better then my math teacher wish me luck for my test tomorrow 🙏

[tinkywinky_teletubby]

Thank you so much, you pointing out abput switching to degree on the calculator saved me so badly!

[saminshohel]

thank so so much u just solved my problem within seconds keep up your good work

[maxpercer]

For those who want the full formula for the area of an n-gon with sides of length s,
by partitioning the regular n-gon into n isosceles triangles with altitude called the apothem (a),
we get area A = 1/2 * s * a * n .
Typically the apothem length is given, but it is not necessary to find the area since by trigonometry
a = s / ( 2 tan (180° / n ) ), and then by substitution (and simplifying)
A = (s^2 * n) / ( 4 tan (180° / n ) ).

[NPERROTTE]

I believe this video helped me to remember what to do using Trigonometry.

[Biz]

brilliant very good at explaining and keeping it simple

[calvinnigh]

Those two dots You left are killing me

[incizor]

Just a small note: those triangles can’t be regular since that means each angle is 60 degrees and you determined that the angle in the centre is 72 degrees. But I guess they are isosceles and bottom angles are (180-72)/2= 108/2= 54 degrees each.

[ArionnaBehounek]

Yall I'm doing this the night before my end of year exam, blud out hear saving lives 😭

[yousifkamaash]

Thank you for these lectures and I have a question about an equal sides Pentagon inscribed inside a triangle the vertix of Pentagon on the base of triangle, the dimensions of the triangle are 77, 106, the base 113 . with my best regards .

[BoiBook]

Very nice! I also did the math like this way!

[onlinethings]

sir thank yo for he help but I never knew pentagrams was going to be this complex lol

[sammeh]

Thank you so much, this helped a lot.

[jimmymchugh]

Cheat draw a oblong box around it then cut out pentagon -assemble surrounding triangles firm them into box minus it from original box =

[subratabhattacharya]

Why did not we use pythogorous theorem to calculate the value of 'a' ??? Please explain ? Is not the value of the hypotenuse is 12 ?

[NarenlynMimari]

Please can you find the height of the Pentagon

[Ooh_Very_Berry]

What if the side is an equation with variables?

[adedoyinoka]

I dont understand it my head will explode 😢 i can't take it anymore 😭, and why did we not just multiply both sides by six rather than crossmultiply it at first

[granttaylor]

I love math class with my teacher mr schaben