What is the area of an equilateral triangle whose one side l

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What is the area of an equilateral triangle whose one side length is 60?

A. 300√3
B. 400√3
C. 450√3
D. 600√3
E. 900√3


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by Brent@GMATPrepNow » Sun Feb 28, 2016 9:17 pm
Max@Math Revolution wrote:What is the area of an equilateral triangle whose one side length is 60?

A. 300√3
B. 400√3
C. 450√3
D. 600√3
E. 900√3
Area of an equilateral triangle = (s²/4)√3, where s = length of one side.
So...

Area = (60²/4)√3
= (3600/4)√3
= 900√3
= E

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Brent
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by Max@Math Revolution » Tue Mar 01, 2016 11:33 pm
What is the area of an equilateral triangle whose one side length is 60?

A. 300√3
B. 400√3
C. 450√3
D. 600√3
E. 900√3


-> The area of an equilateral triangle with one side length of a is √3a2/4. Thus, √3(60^2)/4=900√3 and the answer is E.