Question

(-15) × 8 - (2)⁷

( 8 )
(7)
(-1)
(-20) ​

Answer 1

$\boxed{\begin{array}{l}\sf Numa~express\tilde ao~num\acute erica~resolve-se:\\\sf 1^o~pot\hat encias~e~ra\acute izes~(na~ordem~que~vier) \\\sf 2^o~multiplicac_{\!\!,}\tilde oes~e~divis\tilde oes~(na~ordem~que~vier)\\\sf 3^o~adic_{\!\!,}\tilde oes~e~subtrac_{\!\!,}\tilde oes~(na~ordem~que~vier). \\\sf Al\acute em~disso~eliminamos:\\\sf 1^o~\bigg(~\bigg) \\\sf 2^o~\bigg[~\bigg]\\\sf 3^o~\bigg\{\bigg\} \end{array}}$

$\boxed{\begin{array}{l}\sf(-15)\times8-(2)^7\\\sf (-15)\times8-128\\\sf-120-128=-248\end{array}}$