To find side $ a $ use formula:
$$ r = \dfrac{ \sqrt{ 3 } \cdot a }{ 2 } $$After substituting $ r = 46 $ we have:
$$ 46 = \dfrac{ \sqrt{ 3 } \cdot a }{ 2 } $$ $$ \sqrt{ 3 } \cdot a = 46 \cdot 2 $$ $$ \sqrt{ 3 } \cdot a = 92 $$ $$ a = \dfrac{ 92 }{ \sqrt{ 3 } } $$ $$ a = \frac{ 92 \sqrt{ 3}}{ 3 } $$