Answer:
11.7
Step-by-step explanation:
pythagorean theorem is 
apply that same formula soo 
then sqaure root 136
round that soo now the answer is 11.7
Is the base square or rectangle?
I would choose the formula D (distance to the finish line)=3-2x/2 where x is the distance run so for example for x = 1 km then 2 times 1 = 2/2=1 so D=3-1=2km which is seen to be the logical answer so it seems to corroborate the equation.