[tex]\frac{5(F-32)}{9}\\F=-81,4\\\frac{5(-81,4-32)}{9}=\frac{5*(-113,4)}{9}=\frac{-567}{9}=-63\ [^\circ C]\\F=113\\\frac{5(113-32)}{9}=\frac{5*81}{9}=\frac{405}{9}=45\ [^\circ C]\\[/tex]