Equilateral triangle vs circle

Find the area of an equilateral triangle inscribed in a circle of radius r = 9 cm. What percentage of the circle area does it occupy?

Correct answer:

S =  105.2221 cm2
p =  41.3497 %

Step-by-step explanation:

r=9 cm  a=3/3 r=3/3 9=9 3 cm15.5885 cm  S=34 a2=34 15.58852=105.2221 cm2
S1=π r2=3.1416 92254.469 cm2  p=100 SS1=100 105.2221254.469=41.3497%



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Tips to related online calculators
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See also our trigonometric triangle calculator.

 
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