Starting from a 130 feet away, a person on a bicycle rides towards a checkpoint and then passes it. The rider is traveling at a constant rate of 25 feet per second. The distance between the bicycle and the checkpoint is given by the equation: d = |130 - 25t|. At what times is the bike 15 feet away from the checkpoint?
for this question you can say d = 15 feet so we need the t then you can say : 15 = l 130 - 25t l ⇒ because of the absolute value you should say : 1) 130 - 25t = 15 ⇒ -25t = 15 - 130 ⇒ - 25t = -115 ⇒ t = 115/25 = 4.6 sec
2) 130 - 25t = - 15 ⇒ -25t = -15 - 130 ⇒ -25t = - 145 ⇒ t = 145/25 = 5.8 sec so the answer is c :)) i hope this is helpful have a nice day
