Answer: Tina rides 4 miles and Derek rides 3 miles.
Explanation:
Since we have given that
Distance covered by Derek in west direction be x
Distance covered by Tina in south direction be x+1
Distance between the bikers when they both stop is x+2
Since it forms right triangle, so we will apply "Pythagorus theorem":
Since distance can't be in negative sign, so we take x=3 miles
Derek rides 3 miles
Tina rides is given by
Hence, Tina rides 4 miles and Derek rides 3 miles.