Question

Num triângulo um dos ângulo mede 27°é outro mede 64°. Terceiro ângulo interno mede ?.

Answer 1

$\large\boxed{\begin{array}{l}\underline{\rm A\,soma\,dos\,\hat angulos\,internos}\\\underline{\rm de\,um\,tri\hat angulo\,vale\,180^\circ}\\\sf 27^\circ+64^\circ+x=180^\circ\\\sf x=180^\circ-64^\circ-27^\circ\\\sf x=89^\circ\end{array}}$