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Whitepunk [10]
3 years ago
5

How to find the area of a equilateral triangle that has a perimeter of 21?

Mathematics
1 answer:
Romashka-Z-Leto [24]3 years ago
8 0
First, we have to find the length of each side of triangle. Equilateral triangle means 3 sides r in same length, so each side will be 21 ÷ 3 = 7
Now we need to calculate the height of the triangle. We can do this by Pythagoras theorem
Let the height be h
(7/2)^2 + x^2 = 7^2
The area should be 6.0621778265
Or u can say 6.06 corrected to 3 sig fig
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