Question
Find the side $ a $ of an equilateral triangle if circumcircle radius $R = 7\, \text{cm}$.
Answer
$7 \sqrt{ 3 }\, \text{cm}$
Explanation
To find side $ a $ use formula:
$$ R = \dfrac{ \sqrt{ 3 } \cdot a }{ 3 } $$After substituting $R = 7\, \text{cm}$ we have:
$$ 7\, \text{cm} = \dfrac{ \sqrt{ 3 } \cdot a }{ 3 } $$ $$ \sqrt{ 3 } \cdot a = 7\, \text{cm} \cdot 3 $$ $$ \sqrt{ 3 } \cdot a = 21\, \text{cm} $$ $$ a = \dfrac{ 21\, \text{cm} }{ \sqrt{ 3 } } $$ $$ a = 7 \sqrt{ 3 }\, \text{cm} $$This page was created using
Equilateral Triangle Calculator