• 7 CATs FREE!
If you earn 100 Forum Points

Engage in the Beat The GMAT forums to earn
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 the triangle ABC? tagged by: Vincen ##### This topic has 1 expert reply and 0 member replies ## What is the area of the triangle ABC? What is the area of the triangle ABC? (1) The edge AB of the triangle is 8 inches. (2) Triangle ABC is equilateral The OA is C. How can I find the area just knowing that the triangle is equilateral? Experts, can you help me? I'd appreciate your help here. ### GMAT/MBA Expert Legendary Member Joined 20 Jul 2017 Posted: 503 messages Followed by: 10 members Upvotes: 86 GMAT Score: 770 Top Reply We can work through this problem really quickly if we happen to know that we can solve for the area of an equilateral triangle using: $$A=\frac{\sqrt{3}}{4}a^2$$ where a is the length of one side of the triangle. However, even if we don't know that, we can still solve. We know that all sides of the triangle are 8 inches long because the triangle is equilateral. envision dividing our equilateral triangle in half, giving two right triangles with a base of 4 and a hypotenuse of 8. Using the pythagorean theorem, we can then solve for the height by plugging in $$4^2+h^2=8^2$$ $$h^2=80$$ $$h=4\sqrt{5}$$ Once we fing the height, we can then solve for the area of the equilateral triangle using $$A=\frac{1}{2}bh$$ where b = 8: $$A=\frac{1}{2}8*4\sqrt{5}$$ $$A=16\sqrt{5}$$ So the statements are sufficient together. Of course, we don't actually need to solve for the area, or even the height of the triangle - since this is DS, all we need to do is know that if we know the length of one side on an equilateral triangle, we can find the area and solve the problem. _________________ Erika John - Content Manager/Lead Instructor https://gmat.prepscholar.com/gmat/s/ Get tutoring from me or another PrepScholar GMAT expert: https://gmat.prepscholar.com/gmat/s/tutoring/ Learn about our exclusive savings for BTG members (up to 25% off) and our 5 day free trial Check out our PrepScholar GMAT YouTube channel, and read our expert guides on the PrepScholar GMAT blog • 5-Day Free Trial 5-day free, full-access trial TTP Quant Available with Beat the GMAT members only code • Magoosh Study with Magoosh GMAT prep Available with Beat the GMAT members only code • FREE GMAT Exam Know how you'd score today for$0

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

Available with Beat the GMAT members only code

• Award-winning private GMAT tutoring
Register now and save up to \$200

Available with Beat the GMAT members only code

• 1 Hour Free
BEAT THE GMAT EXCLUSIVE

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

• 5 Day FREE Trial
Study Smarter, Not Harder

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

### Top First Responders*

1 Brent@GMATPrepNow 64 first replies
2 fskilnik@GMATH 58 first replies
3 Jay@ManhattanReview 46 first replies
4 GMATGuruNY 34 first replies
5 Rich.C@EMPOWERgma... 24 first replies
* Only counts replies to topics started in last 30 days
See More Top Beat The GMAT Members

### Most Active Experts

1 fskilnik@GMATH

GMATH Teacher

120 posts
2 Brent@GMATPrepNow

GMAT Prep Now Teacher

99 posts
3 Max@Math Revolution

Math Revolution

88 posts
4 Jay@ManhattanReview

Manhattan Review

82 posts
5 Rich.C@EMPOWERgma...

EMPOWERgmat

65 posts
See More Top Beat The GMAT Experts