This question I just can't get...

Question

Stopping distance, d, measured in feet, of a car travelling at v miles per hour is given by this formula:  

          

d = v + v ² 

                20

 

Find d when v = 20 miles per hour

                            
               

                               

 

(v2/20 is supposed to be a fraction, have no idea what happened with the formatting)

Answer 1

d = v + v² / 20

d = 20 + 20² / 20

d = 20 + 20

d = 40