To find area $ A $ use formula:
$$ A = \dfrac{ a \cdot a \cdot \sin( \alpha ) }{ 1 } $$After substituting $ a = 12 $ , $ a = 12 $ and $ \alpha = 30^o $ we have:
$$ A = \dfrac{ 12 \cdot 12 \cdot \sin( 30^o ) }{ 1 } $$ $$ A = \dfrac{ 12 \cdot 12 \cdot \frac{ 1 }{ 2 } }{ 1 } $$ $$ A = \dfrac{ 144 \cdot \frac{ 1 }{ 2 } }{ 1 } $$ $$ A = \dfrac{ 72 }{ 1 } $$ $$ A = 72 $$