# Trig question help (Determining length)

• Nov 13th 2009, 11:04 AM
agent2421
Trig question help (Determining length)
can someone please help me out.... I have a question and yes it's for homework but I have no idea on how to even begin it.... To me it looks like they already gave the answer or something but I'm not sure how to start or how to do it... Can someone please help me out.

Determine the length of each unknown variable:

How do I solve this? I have no idea on where to even begin... If someone can help me it will be greatly appreciated... I can't show the work I've alreayd done because I don't know how to do this..

Thanks for all the help though if you can answer this

Alright I tried to re-edit it... does it work now?
• Nov 13th 2009, 11:41 AM
bigwave
in a circle of radis r of angle of radian measure $\theta$

subtends an arc of lenght $s = r\theta$

this basically what you need to know to solve this
• Nov 13th 2009, 01:00 PM
agent2421
I still don't understand how to solve this... can you go a litlte more in depth than that?

A) = 3.142

because maybe this is why I'm confused... I was given this question to solve but below the 2 pictures it had those which I think are already the answers....
• Nov 13th 2009, 01:27 PM
bigwave
ok the first is
$
a = \frac{\pi}{3}*3 = \pi \ or \ 3.142 \ cm
$

the second one is
just subtracting $\theta$ from $2\pi$
$
\theta = \frac{2}{4} = \frac{1}{2}
$

$
2\pi - \frac{1}{2} = 5.783\ rad
$
• Nov 13th 2009, 02:09 PM
agent2421
thank you so much! I understand it now.