Question

ache as raízes
- f(x) = - x2 + 16

Answer 1

$\large\begin{array}{l}\hspace{-5}-f(x)=-x^2+16~\Leftrightarrow~f(x)=x^2-16\\\\\\x^2-16=0\\\\x^2=16\\\\ \sqrt{x^2}=\sqrt{16}\\\\\fbox{ x=\pm~4 }\\\\\\\therefore~~x=\left\{\begin{matrix}+4\\\\ou\\\\-4 \end{matrix}\right.\end{array}$