First, we will use the Pythagorean theorem to compute the hypotenuse:
[tex]\begin{gathered} h^2=(6.5m)^2+(2.6m)^2 \\ =42.25m^2+6.76m^2 \\ =49.01m^2. \end{gathered}[/tex]Then:
[tex]h\approx7.0m.[/tex]Therefore, the sail master will need:
[tex]6.5m+2.6m+7m=16.1m[/tex]of blinding.
Answer: 16.1m