[tex]b.)\:22[/tex]
1) We can solve this problem, by using the Pythagorean Relation. So, let's do it.
[tex]\begin{gathered} a^2=b^2+c^2 \\ \\ a^2=19^2+11^2 \\ \\ a^2=361+121 \\ \\ a^2=482 \\ \\ a=\sqrt{482} \\ \\ a=21.95\approx22 \end{gathered}[/tex]
Note that the line segment AC is the hypotenuse (the largest side).
2) Thus, the answer is:
[tex]22[/tex]
