Okay, here we have this:
Considering the provided triangle which is a right triangle, we are going to use the pythagorean theorem to find the measure of the missing side, so we obtain the following:
[tex]\begin{gathered} h^{}=\sqrt[]{a^2+b^2} \\ x=\sqrt[]{35^2+12^2} \\ x=\sqrt[]{1225+144} \\ x=\sqrt[]{1369} \\ x=37 \end{gathered}[/tex]
Finally we obtain that the correct answer is the first option.
