SOLUTION: Find the area of an equilateral triangle (regular 3-gon) with the given measurement. 3-inch radius A = sq. in. please help i got 27/8 sqrt(3) am i correct or do i need

Algebra ->  Polygons -> SOLUTION: Find the area of an equilateral triangle (regular 3-gon) with the given measurement. 3-inch radius A = sq. in. please help i got 27/8 sqrt(3) am i correct or do i need       Log On


   

Question 621294: Find the area of an equilateral triangle (regular 3-gon) with the given measurement.
3-inch radius
A = sq. in.
please help
i got
27/8 sqrt(3)
am i correct or do i need to look at it again
Answer by tomlaidlaw(14) About Me  (Show Source):
You can put this solution on YOUR website!
I think it is twice your answer.
to get the side we use the formula for Radius and manipulate it to get side. Ris given as 3
R+=+sqrt%283%29%2A+side%2F3
3+=+sqrt%283%29+%2A+side%2F3
9+=+sqrt%283%29+%2A+side
side+=+9%2Fsqrt%283%29
side+=+5.19
Then
Area+=sqrt%283%29%2Aside%5E2%2F4
which works out to about 11.664, which is very nearly 27/4 sqrt(3)
There are many good articles on the web. For this answer I relied on:
http://en.wikipedia.org/wiki/Equilateral_triangle