To find side $ a $ use formula:
$$ V = \dfrac{ \sqrt{ 3 } \cdot a ^{ 2 } \cdot l }{ 2 } $$After substituting $ V = 4495.4 $ and $ l = 19 $ we have:
$$ 4495.4 = \dfrac{ \sqrt{ 3 } \cdot a ^{ 2 } \cdot 19 }{ 2 } $$$$ 4495.4 \cdot 2 = \sqrt{ 3 } \cdot a ^{ 2 } \cdot 19 $$$$ 8990.8 = \sqrt{ 3 } \cdot a ^{ 2 } \cdot 19 $$$$ 8990.8 = 19 \sqrt{ 3 } \cdot a ^{ 2 } $$$$ a ^{ 2 } = \dfrac{ 8990.8}{ 19 \sqrt{ 3 } } $$$$ a ^{ 2 } = 273.2021 $$$$ a = \sqrt{ 273.2021 } $$$$ a = 16.5288 $$