Hello!
When the cyclist starts,the runner will have already ran 8 miles. We can write this equation below, where h represents the hours run since the cyclist took off.
14h=8+4h
Let's move the variables onto one side. First we subtract 4h from both sides.
10h=8
Now we divide both sides by 8.
1.25
As you can see, it will take 1.25 hours for the cyclist to overtake the runner.
I hope this helps!