Question 772828
Pythagoras.
A right angled triangle with
vertical side = 11 and base side 
= 17.
The distance from starting point
is the hypotenuse.
Hypotenuse^2 = 11^2 + 17^2
Hypotenuse^2 = 121 + 289
Hypotenuse^2 = 410
Hypotenuse = {{{sqrt(410)}}}
Hypotenuse = 20.3
The distance = 20.3 miles.
Hope this helps.
:-)