Remember that the pythagorean theorem says that:
[tex]a^2+b^2=c^2[/tex]Clearing a:
[tex]\begin{gathered} a^2+b^2=c^2 \\ \rightarrow a^2=c^2-b^2 \\ \rightarrow a=\sqrt[]{c^2-b^2} \end{gathered}[/tex]Using the data given,
[tex]\begin{gathered} a=\sqrt[]{42^2-27^2} \\ \Rightarrow a=32.2 \end{gathered}[/tex]Therefore, a = 32.2
