To find area $ A $ use formula:

$$ A = \dfrac{ a \cdot a \cdot \sin( \alpha ) }{ 1 } $$

After substituting $a = 6\, \text{cm}$, $a = 6\, \text{cm}$ and $\alpha = 60^o$ we have:

$$ A = \dfrac{ 6\, \text{cm} \cdot 6\, \text{cm} \cdot \sin( 60^o ) }{ 1 } $$ $$ A = \dfrac{ 6\, \text{cm} \cdot 6\, \text{cm} \cdot \frac{\sqrt{ 3 }}{ 2 } }{ 1 } $$ $$ A = \dfrac{ 36\, \text{cm}^2 \cdot \frac{\sqrt{ 3 }}{ 2 } }{ 1 } $$ $$ A = \dfrac{ 18 \sqrt{ 3 }\, \text{cm}^2 }{ 1 } $$ $$ A = 18 \sqrt{ 3 }\, \text{cm}^2 $$

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