SOLUTION: The perimeter of an equilateral triangle is 18. Find its area.

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Question 141066This question is from textbook Basic mathematical skills with geometry
: The perimeter of an equilateral triangle is 18. Find its area. This question is from textbook Basic mathematical skills with geometry

Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
An equilateral triangle has 3 equal sides.
Thus there are 3x=18 where x=18/3 or x=6 the length of each sides.
area=bh/2
3^2+x^2=6^2
9+x^2=36
x^2=36-9
x^2=27
x=sqrt27
x=5.196 length of the height.
area=6*5.196/2
area=31.177/2
area=15.29 answer for the area.