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# Algebra/Area of a sector

Question
QUESTION: Hello,

What are the steps in finding the area of a sector? The question states, "find the area of a sector with the given central angle 'a' in a circle of radius 'r'. a=2, r=10 inches

I think the '2' is 2 degrees.

Thanks

ANSWER: The area of a circle is pi(r^2) and there are 360 degrees in a circle so in this case you have
Area = (pi)(10^2)(2/360) = 1.75  sq. inches

---------- FOLLOW-UP ----------

QUESTION: Hi,

Unfortunately that wasn't one of the answers given for the question. The question I sent was multiple-choice, and the choices for the question were 10, 20, 200, or 100 sq in.

If you had told me that at first I could have figured out that angle 'a' had to be in radians.
There are 2pi radians in a circle so you have (pi)(10^2)[2/(2pi)] = 100 sq. in.

I didn't mean to not seem polite.  It's just being polite to us if you send us all the information you have when you ask a question.

Algebra

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#### Richard J. Raridon

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I can answer questions in physics, chemistry, algebra, trigonometry