In the figure attached, equilateral triangle ABC is inscribed in the circle. If the length of arc ABC=24, what is the approximate diameter of the circle?
5
8
11
15
19
11
5
8
11
15
19
11
- Attachments
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I assumed the perimeter of the triangle to be 24; which gives
AB = BC = AC = 8
Image attached!
Draw a perpendicular from A so that is bisects B & C at point D and where it touches the circle as point E.
BD = CD = 4
as AB = 8, BD = 4,
Using pythagoras, AD approx is 7
Lets take center of the circle as O,
OD = DE = 3.5
AE = AD + DE
= 7 + 3.5
= 10.5 Approx 11
Please comment.
Ans C.
