Question

Given a triangle with b = 7 c = 3 and A = 37 degrees, what is the length of a?

Answer 1

sounds like a job for the law of cosines...

http://www.mathsisfun.com/algebra/trig-cosine-law.html

Answer 2

I did that, but I keep getting an answer that isn't an answer choice

Answer 3

what did you get?

Answer 4

6.5

Answer 5

okay, just a sec...

Answer 6

\[a^2=b^2+c^2-2bc \cos A= 7^2+3^2-2(7)(3)\cos 37^{\circ}=49+9-42(.7986355...)\]
\[=24.457308...\Rightarrow a=\sqrt{a^2}=\sqrt{24.457308...}=4.945433103...\]

Answer 7

did you find your mistake?

Answer 8

Yeah I did. Thank you so much

Answer 9

you're welcome!