Answer
$T(x)=\frac{\sqrt {x^2+4}}{2}+\frac{6-x}{5}$ hours
Work Step by Step
Step 1. Using the figure given in the exercise, with the Pythagorean Theorem, the distance of rowing on water is given by $\sqrt {x^2+2^2}$ miles and the time for this part is $\frac{\sqrt {x^2+4}}{2}$ hours.
Step 2. For the second part, the distance of jogging is $6-x$ miles and the time needed is $\frac{6-x}{5}$ hours
Step 3. The total time needed is given by $T(x)=\frac{\sqrt {x^2+4}}{2}+\frac{6-x}{5}$ hours