Angles and Radian Measures

topaz192 · #1 $Old$ 09-02-2008, 07:13 PM

I tried to find some help online but I havent found any yet. :[
How do you find the radius of a circle if an arc is 14.2 cm long and is intercepted by a central angle of 60 degrees.

I know the formula for it when there is a radius. But since there isnt i have no clue. Please help!

ur5pointos2slo · #2 $Old$ 09-02-2008, 07:54 PM

What is the formula you are using?

vinson24 · #3 $Old$ 09-02-2008, 07:57 PM

try r=s/central angle other words radius equals arc length divided by central angle

Moo · #4 $Old$ 09-03-2008, 04:26 AM

Hello,

Quote:

Originally Posted by topaz192 $View Post$

I tried to find some help online but I havent found any yet. :[
How do you find the radius of a circle if an arc is 14.2 cm long and is intercepted by a central angle of 60 degrees.

I know the formula for it when there is a radius. But since there isnt i have no clue. Please help!

$angles-radian-measures-cercle.jpg$

Shyam · #5 $Old$ 09-03-2008, 09:03 PM

Quote:

Originally Posted by topaz192 $View Post$

I tried to find some help online but I havent found any yet. :[
How do you find the radius of a circle if an arc is 14.2 cm long and is intercepted by a central angle of 60 degrees.

I know the formula for it when there is a radius. But since there isnt i have no clue. Please help!

arc a=14.2 cm
angle $\theta=60$

$\theta=60.\frac{\pi}{180}\;radian$

$\theta=1.0472\;radian$

$a=r.\theta$

$r=\frac{a}{\theta}$

$r=\frac{14.2}{1.0472}$

r=13.56 cm