How fast did each hiker walk if they meet in 2 hours?

Question

Two hikers start from the same point and hike in opposite directions around a lake whose shoreline is 13 miles long. One hiker walks 0.5 mph faster than the other hiker. How fast did each hiker walk if they meet in 2 hours?  How do I set up this equation?

Answer 1

distance=rate*time

d=r*t

13=r*2+(r+0.5)*2

13=2r+2r+2(0.5)

13=4r+1

13-1=4r

12=4r

r=12/4

r=3 mph

r+0.5=3.5 mph