Solution
We want to find the length CD to the nearest tenth
From the diagram, the length CD is the diagonal of the square of sides 9cm
We therefore, find the length by pythagoras theorem
[tex]\begin{gathered} Hyp^2=Opp^2+Adj^2 \\ \\ Hyp=\sqrt{Opp^2+Adj^2} \\ \\ CD^=\sqrt{9^2+9^2} \\ \\ CD=\sqrt{81+81} \\ \\ CD=9\sqrt{2} \\ \\ CD=12.72792206 \\ \\ CD=12.7cm\text{ \lparen to the nearest tenth\rparen} \end{gathered}[/tex]
