SOLUTION: what is the area of an equilateral triangle if each side measures 18 dm long?

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Question 701426: what is the area of an equilateral triangle if each side measures 18 dm long?
Answer by shanehhhh47(5) About Me  (Show Source):
You can put this solution on YOUR website!
There are many methods in solving this, but I recommend this formula:
A=s^2((sqrt of 3)/4)
Substitute:
A=(18)^2 ((sqrt of 3)/4)
A=324(sqrt of 3)/4
simplify: 324/4
81 sqrt of 3 dm^2 is the answer or if you want a more precise answer:
140.296115413dm^2
:)