Find the area of the regular polygon. Give the answer to the nearest tenth. decagon with a side of 4 cm
A. 123.1 cm2
B. 129.4 cm2
C. 246.2 cm2
D. 139.8 cm2

Question

Find the area of the regular polygon. Give the answer to the nearest tenth. decagon with a side of 4 cm
  A. 123.1 cm2 	
  B. 129.4 cm2 	
  C. 246.2 cm2 	
  D. 139.8 cm2

ganeshie8 · Answer

Area of regular polygon of side length $s$  :

 $\large    \dfrac{ns^2}{4} \cot (\frac{\pi}{n})$

ganeshie8 · Answer

simply plugin $s$, $n$ values
and evaluate

anonymous · Answer

n = number of sides
s = length of side

anonymous · Answer

ohhh thanks for clarifying batman

anonymous · Answer

Np, so give this a shot, and get back to us :P

anonymous · Answer

Actually since we're using a decagon you can easily just use this:

$$A = \frac{ 5 }{ 2 }a^2\sqrt{5+2\sqrt{5}}$$

Where a is the side.

anonymous · Answer

40^2/4 =400

anonymous · Answer

decagon has 10 sides

anonymous · Answer

It's A !

anonymous · Answer

Correcto!