The Solution.
By intersecting secant theorem, we have that,
[tex]\begin{gathered} |BA|^2=|BC|\times|BD| \\ x^2=20\times36 \end{gathered}[/tex]Taking the square root of both sides, we get
[tex]\begin{gathered} x=\sqrt[]{720} \\ x=6\times2\sqrt[]{5} \\ x=12\sqrt[]{5}\text{ or 26.83} \end{gathered}[/tex]The correct answer is 26.83
