Question

Please help! Click on attachment to view please :O

Answer 1

Do you know how to find Sin(A) and Tan(A)?

Answer 2

where is the data?

Answer 3

You have to find A first. and then use the half angle theorems

Answer 4

take -ArchCos(2/5) which gives you -x degrees. Then divide it by 2 so you get -(1/2)x
then it will give you A/2, and just take sin of it and you have the answer.

Answer 5

Thanks guys, wish I could give more than one medal :/

Answer 6

As long as you give it to me, i'm happy :P
Also, Remember to close the question.