Question

Roma sherry drove 80 miles from her home town to her​ parents' town. during her return​ trip, she was able to increase her speed by 44 miles per hour. if her return trip took 1 hour less​ time, find her original speed and her speed returning home.

Answer 1

Answer: Roma Sherry drove 330 miles from her hometown to Tucson. During her return trip, she was able to increase her speed by 11 mph. If her return trip took 1 hour less time, find her original speed and her speed returning home. : Let s = original speed then (s+11) = return speed : Write a time equation: Time = distance%2Fspeed : Original time = return time + 1 hr 330%2Fs = 330%2F%28%28s%2B11%29%29 + 1 : Multiply equation by s(s+11) and you have: 330(s+11) = 330s + s(s+11) : 330s + 3630 = 330s + s^2 + 11s : 0 = 330s - 330s + s^2 + 11s - 3630 : A quadratic equation: s^2 + 11s - 3630 = 0 Factor this to: (s + 66)(s - 55) = 0 Positive solution s = 55 mph is original speed. : Find the time 330/55 = 6 hr, original time and 330/66 = 5 hrs, faster time; confirms our solution.