A dodecagon

Find the surface area of a regular 12-sided polygon if its side is a = 12 cm.

Correct answer:

S =  1612.2459 cm2

Step-by-step explanation:

a=12 cm n=12  α=360/n=360/12=30  β=α/2=30/2=15  tan β =  ha/2  h=tan(β)a/2=tan(15°)12/222.3923 cm  S1=2h a=222.3923 12134.3538 m2 S=n S1=12 134.3538=1612.2459 cm2



Did you find an error or inaccuracy? Feel free to write us. Thank you!







Tips for related online calculators
Need help calculating sum, simplifying, or multiplying fractions? Try our fraction calculator.
See also our right triangle calculator.
See also our trigonometric triangle calculator.

You need to know the following knowledge to solve this word math problem:


 
We encourage you to watch this tutorial video on this math problem: video1

Related math problems and questions: