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100 points for $49 worth of Veritas practice GMATs FREE VERITAS PRACTICE GMAT EXAMS Earn 10 Points Per Post Earn 10 Points Per Thanks Earn 10 Points Per Upvote ## What is the area of an equilateral triangle... tagged by: AAPL ##### This topic has 2 expert replies and 0 member replies ### Top Member ## What is the area of an equilateral triangle... What is the area of an equilateral triangle whose one side length is 60? A. 300β3 B. 400β3 C. 450β3 D. 600β3 E. 900β3 The OA is E. I know that I can get the height of the triangle using Pythagoras Theorem, then $$h_{\triangle}=\sqrt{60^2-30^2}=30\sqrt{3}$$ Then, I can get the area of the triangle, $$A_{\triangle}=\frac{1}{2}b\cdot h$$ $$A_{\triangle}=\frac{1}{2}b\cdot h=\frac{1}{2}\cdot60\cdot30\sqrt{3}=900\sqrt{3}$$ But, is there another strategic approach to this question? Can any experts help please? Thank you! ### GMAT/MBA Expert GMAT Instructor Joined 04 Oct 2017 Posted: 551 messages Followed by: 11 members Upvotes: 180 Top Reply Quote: What is the area of an equilateral triangle whose one side length is 60? A. 300β3 B. 400β3 C. 450β3 D. 600β3 E. 900β3 The OA is E. Hi AAPL, Let's take a look at your question. Area of equilateral triangle can be calculated as: $$Area=\frac{s^2\sqrt{3}}{4}$$, where s is the side length of the equilateral triangle. $$Area=\frac{\left(60\right)^2\sqrt{3}}{4}$$ $$Area=\frac{3600\sqrt{3}}{4}$$ $$Area=900\sqrt{3}$$ Therefore, Option E is correct. Hope it helps. I am available if you'd like any follow up. _________________ GMAT Prep From The Economist We offer 70+ point score improvement money back guarantee. Our average student improves 98 points. Free 7-Day Test Prep with Economist GMAT Tutor - Receive free access to the top-rated GMAT prep course including a 1-on-1 strategy session, 2 full-length tests, and 5 ask-a-tutor messages. Get started now. ### GMAT/MBA Expert GMAT Instructor Joined 08 Dec 2008 Posted: 13036 messages Followed by: 1251 members Upvotes: 5254 GMAT Score: 770 AAPL wrote: What is the area of an equilateral triangle whose one side length is 60? A. 300β3 B. 400β3 C. 450β3 D. 600β3 E. 900β3 Area of an equilateral triangle = (sΒ²/4)(β3) (where s = length of one side) So... Area = (60Β²/4)(β3) = (3600/4)(β3) = 900β3 = E Cheers, Brent _________________ Brent Hanneson β Creator of GMATPrepNow.com Use my video course along with Sign up for free Question of the Day emails And check out all of these free resources GMAT Prep Now's comprehensive video course can be used in conjunction with Beat The GMATβs FREE 60-Day Study Guide and reach your target score in 2 months! • 1 Hour Free BEAT THE GMAT EXCLUSIVE Available with Beat the GMAT members only code • Magoosh Study with Magoosh GMAT prep Available with Beat the GMAT members only code • Free Veritas GMAT Class Experience Lesson 1 Live Free Available with Beat the GMAT members only code • Free Practice Test & Review How would you score if you took the GMAT Available with Beat the GMAT members only code • 5-Day Free Trial 5-day free, full-access trial TTP Quant Available with Beat the GMAT members only code • Free Trial & Practice Exam BEAT THE GMAT EXCLUSIVE Available with Beat the GMAT members only code • Get 300+ Practice Questions 25 Video lessons and 6 Webinars for FREE Available with Beat the GMAT members only code • Award-winning private GMAT tutoring Register now and save up to$200

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