SOLUTION: Given: ΔABC, AB = BC = AC= a. Find: The area of ΔABC

Algebra ->  Surface-area -> SOLUTION: Given: ΔABC, AB = BC = AC= a. Find: The area of ΔABC      Log On


   

Question 1104721: Given: ΔABC, AB = BC = AC= a. Find: The area of ΔABC
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
It's an equilateral triangle with sides = a
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base b = a
Height h = sqrt(a^2 - (a/2)^2) = a*sqrt(3)/2
Area+=+b%2Ah%2F2+=+a%5E2%2Asqrt%283%29%2F4
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For any regular polygon with n sides = s:
Area = ns^2*cot(180/n)/4
= 3a^2*cot(60)/4
= a^2*sqrt(3)/4 ---- same answer