Assuming you meant the x2 as x squared, then:
(11x+4)(11x-4)
Answer:
2000+600+9+.75 maybe?
Step-by-step explanation:
Answer:
41.68 or 42 (rounded)
Step-by-step explanation:
Presuming you are working on right triangles, you can use the Soh Cah Toa theorems.
Because angle A = 21 and side a = 16 you can use Toa or 

Plugged into a calculator, you get 41.68 and some change.
If this is NOT a right triangle question, please let me know so that I can revise my answer.
Answer:
Step-by-step explanation:
13*3=39ft (if thats what ur looking for)