Last visit was: 22 Nov 2024, 19:16 It is currently 22 Nov 2024, 19:16

Close

GRE Prep Club Daily Prep

Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GRE score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Close

Request Expert Reply

Confirm Cancel
Verbal Expert
Joined: 18 Apr 2015
Posts: 30003
Own Kudos [?]: 36355 [0]
Given Kudos: 25927
Send PM
Verbal Expert
Joined: 18 Apr 2015
Posts: 30003
Own Kudos [?]: 36355 [0]
Given Kudos: 25927
Send PM
Retired Moderator
Joined: 10 Apr 2015
Posts: 6218
Own Kudos [?]: 12196 [0]
Given Kudos: 136
Send PM
User avatar
Senior Manager
Senior Manager
Joined: 10 Feb 2020
Posts: 496
Own Kudos [?]: 349 [0]
Given Kudos: 299
Send PM
Re: In the figure above, PQ is a diameter of circle O, PR = SQ, [#permalink]
Hi Brent,just 1 question. If we know this is equilateral triangle means all sides and angles are equal, and we got one side also that is x=1 so cant we just compare 1=2x ? why do we have to compare 1=x root3 if sides are equal?

GreenlightTestPrep wrote:
Carcass wrote:
Image
In the figure above, PQ is a diameter of circle O, PR = SQ, and ΔRST is equilateral. If the length of PQ is 2, what is the length of RT ?

A. \(\frac{1}{2}\)

B. \(\frac{1}{\sqrt{3}}\)

C. \(\frac{\sqrt{3}}{2}\)

D. \(\frac{2}{\sqrt{3}}\)

E. \(\sqrt{3}\)

GIVEN: The length of PQ is 2
In other words, the DIAMETER = 2
From this, we can conclude that the RADIUS = 1
So, we can add this information to our diagram:
Image


Since ΔRST is equilateral, we know the altitude (TO) will be a perpendicular bisector of side RS
Also, since ΔRST is equilateral, we know that ∠ORT = 60°, which also means ∠RTO = 30°
Image

At this point, we can see that ΔTRO is a special 30-60-90 triangle.
If we compare ΔTRO with the BASE 30-60-90 triangle, we can create an equation by comparing corresponding sides

We can write: x/2 = 1/(√3)

Multiply both sides by 2 to get: x = 2/(√3)

Answer: D
Prep Club for GRE Bot
Re: In the figure above, PQ is a diameter of circle O, PR = SQ, [#permalink]
Moderators:
GRE Instructor
84 posts
GRE Forum Moderator
37 posts
Moderator
1111 posts
GRE Instructor
234 posts

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne