use the pythagorean theorem to find the missing length in the right angle

Now according to pythagorean theorem we have
[tex]\begin{gathered} c^2=(5)^2+(12)^2 \\ c^2=25+144 \\ c^2=169 \\ c=\sqrt[]{169} \\ c=13 \end{gathered}[/tex]Hence the value of c is 13.