According to the image, the given triangle is a right triangle, it means, you can use the pythagorean theorem to solve this problem.
Hypotenuse=11.2
Leg1=8.5
Leg2=x
[tex]\begin{gathered} l2=\sqrt[]{h^2-l1^2} \\ l2=\sqrt[]{11.2^2-8.5^2} \\ l2=7.3 \end{gathered}[/tex]x has a value of 7.3.