Respuesta:
[tex]-1.25786\dots[/tex]
Explicación paso a paso:
[tex]\frac{28-6^2}{9+\sqrt{81}\cdot \:0.2^2-3}\\\\\frac{-8}{9+\sqrt{81}\cdot \:0.2^2-3}\\\\\frac{-8}{6+\sqrt{81}\cdot \:0.04}\\\\-\frac{8}{6+\sqrt{81}\cdot \:0.04}\\\\-\frac{8}{6+0.36}\\\\-\frac{8}{6.36}\\\\-1.25786\dots[/tex]
