[tex]\bf \textit{using the pythagorean theorem} \\\\ c^2=a^2+b^2\implies c=\sqrt{a^2+b^2} \qquad \begin{cases} c=hypotenuse\\ a=\stackrel{adjacent}{5}\\ b=\stackrel{opposite}{12}\\ \end{cases} \\\\\\ c=\sqrt{5^2+12^2}\implies c=\sqrt{169}\implies c=13[/tex]
