¡Hola!
[tex] \bigstar \: - \big( \dfrac{3}{ 4} { \big)}^{2} \\ \\ \star = - \dfrac{ {3}^{2} }{ {4}^{2} } \\ \\ \boxed{\star = \boxed{- \dfrac{9}{16} }} \\ \\ \bigstar \big( - \dfrac{3}{4} {\big)}^{2} \\ \\ { \big( - \dfrac{3}{ 4} \big) ^{2} \rightarrow \big( \dfrac{3}{ 4} { \big)}^{2}} \\ \\ \star= \dfrac{ {3}^{2} }{ {4}^{2} } \\ \\ \boxed{ \star = \boxed{ \dfrac{9}{16}}}[/tex]
Espero que sirva y saludos.
