May 10th, 2019, 09:15 AM  #1 
Newbie Joined: Apr 2019 From: Malawi Posts: 9 Thanks: 0 Math Focus: Trigonometry and calculus  Circle Trigonometry
The area of a circle is 15 cm^2 and the length of its arc is 3 cm. Calculate the radius of the sector and its angle. May somebody help please 
May 10th, 2019, 10:04 AM  #2 
Global Moderator Joined: Dec 2006 Posts: 20,623 Thanks: 2076 
If the radius of the circle is $r$ cm, $\pi r^2 = 15$, so $r = \sqrt{15/\pi}$. The radius of the sector is also $r$ cm. The angle of the sector (in radians) is $3/r$. 
May 10th, 2019, 11:31 AM  #3 
Newbie Joined: Apr 2019 From: Malawi Posts: 9 Thanks: 0 Math Focus: Trigonometry and calculus 
Thank you


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