To find side $ c $ use Law of Cosines:
$$ c^2 = a^2 + b^2 - 2 \cdot a \cdot b \cdot \cos( \gamma ) $$After substituting $a = 563$, $b = 490$ and $\gamma = 73^o$ we have:
$$ c^2 = 563^2 + 490^2 - 2 \cdot 563 \cdot 490 \cdot \cos( 73^o ) $$ $$ c^2 = 316969 + 240100 - 2 \cdot 563 \cdot 490 \cdot \cos( 73^o ) $$ $$ c^2 = 557069 - 2 \cdot 275870 \cdot \cos( 73^o ) $$ $$ c^2 = 557069 - 551740 \cdot 0.2924 $$ $$ c^2 = 557069 - 161313.1644 $$ $$ c^2 = 395755.8356 $$ $$ c = \sqrt{ 395755.8356 } $$$$ c \approx 629.0913 $$