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#### Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here. # Point O is the center of the semicircle. If ∠ BCO = 30 ° and  Question banks Downloads My Bookmarks Reviews Important topics
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Point O is the center of the semicircle. If ∠ BCO = 30 ° and [#permalink]
Expert's post 00:00

Question Stats: 100% (03:31) correct 0% (00:00) wrong based on 11 sessions
Point O is the center of the semicircle. If ∠ BCO = 30 ° and $$BC = 6 \sqrt{3}$$ what is the area of triangle ABO?

Attachment: GRE exam - Point O is the center of the semicircle..jpg [ 9.5 KiB | Viewed 1472 times ]

A. $$4 \sqrt{3}$$

B. $$6 \sqrt{3}$$

C. $$9 \sqrt{3}$$

D. $$12 \sqrt{3}$$

E. $$24 \sqrt{3}$$
[Reveal] Spoiler: OA

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Last edited by Carcass on 03 Dec 2018, 11:13, edited 1 time in total.
Edited by Carcass Intern Joined: 15 Sep 2018
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Re: Point O is the center of the semicircle. If ∠ BCO = 30 ° and [#permalink]
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This post received
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Missing information from the prompt.

Should state: BC = 6√3
Founder  Joined: 18 Apr 2015
Posts: 6643
Followers: 107

Kudos [?]: 1274 , given: 6003

Re: Point O is the center of the semicircle. If ∠ BCO = 30 ° and [#permalink]
Expert's post
Thank you so much. Did not show up.

Regards
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Re: Point O is the center of the semicircle. If ∠ BCO = 30 ° and [#permalink]
Expert's post
Carcass wrote:
Point O is the center of the semicircle. If ∠ BCO = 30 ° and $$BC = 6 \sqrt{3}$$ what is the area of triangle ABO?

Attachment:
GRE exam - Point O is the center of the semicircle..jpg

A. $$4 \sqrt{3}$$

B. $$6 \sqrt{3}$$

C. $$9 \sqrt{3}$$

D. $$12 \sqrt{3}$$

E. $$24 \sqrt{3}$$

triangle ABC is a right angled triangle at A, and ∠ BCO = 30 °, so ABC is 30-60-90 triangle and sides are in ratio 1:$$\sqrt{3}$$:2
now opposite 60 is side $$BC = 6 \sqrt{3}$$, so AB=6 and AC=12=2*radius.... radius = 6

Let us see OAB..
As we can see AB=6 and OA=OB=radius=6
so it is an equilateral triangle with side 6..
area = $$(\sqrt{3}/4)*6^2=9\sqrt{3}$$

C
_________________

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5. Absolute Modulus and Inequalities : https://greprepclub.com/forum/absolute-modulus-a-better-understanding-11281.html Re: Point O is the center of the semicircle. If ∠ BCO = 30 ° and   [#permalink] 03 Dec 2018, 19:26
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