Hello everyone,

I was wondering if someone could help me with this question?

I solved it by assuming the triangle was equilateral, and took the area. Then I used the following formula:

[(area of sector)/(area of circle)] = [(degree of sector)/(360)]

The number I got was big and so I just multiplied each option to see which was closest. I am pretty sure I wasn’t suppose to assume that the triangle was equilateral.

Any help would be greatly appreciated!

O is center thus, It make OA and OB its radius(OA=OB). Now, angle opposite to equal sides are also equal ,so, you can now use interior angle of a triangle must add upto 180 to find the remaining angle-> 60 +x+x = 180 (After this you basically have your answer because you will get the length of the radius! ).

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I think you are probably misunderstanding AB=10 as the length of arc AB

It is actually the length of side of the triangle ABC.

Moreover, I think your approach for considering the triangle as equilateral is completely fine as it is an equilateral triangle.

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Thank you! That makes a lot of sense!

That you for helping me. It definitely cleared up my misunderstanding!