how do you find an area for a pentagonal prism

2 answers

Look it up!
Since this is not my area of expertise, I searched Google under the key words "area pentagonal prism" to get this:

http://www.google.com/search?client=safari&rls=en&q=area+pentagonal+prism&ie=UTF-8&oe=UTF-8

In the future, you can find the information you desire more quickly, if you use appropriate key words to do your own search. Also see http://hanlib.sou.edu/searchtools/.