1. Round-Trip Travel Sarah drives into the city to buy a software program at a computer store. Because of traffic conditions, she averages only 15 mi/h. On her drive home she averages 35 mi/h. If the total travel time is 2 hours, how long does it take her to drive to the computer store? Define: Let t = time of Sarah’s drive to the computer store. 2 – t = time of Sarah’s drive home. Relate: Part of Sarah’s travel RateTimeDistance To the computer store 15 t15t Return home 35 2 – t35(2 – t)

2. Round-Trip Travel Write:15t = 35(2 – t) 15t = 70 – 35t +35t + 35t 50t = 70 t = 1.4 It took Sarah 1.4 h to drive to the computer store.

3. Opposite-Direction Travel Jane and Peter leave their home traveling in opposite directions on a straight road. Peter drives 15 mi/h faster than Jane. After 3 hours, they are 225 miles apart. Find Peter’s rate and Jane’s rate. Define: Let r = Jane’s rate Then r + 15 = Peter’s rate Relate: PersonRateTimeDistance Jane r33r Peter r + 1533(r + 15)

4. Opposite-Direction Travel Write:3r + 3(r + 15) = 225 3r + 3r + 45 = 225 6r + 45 = 225 - 45 - 45 6r = 180 r = 30 Jane’s rate is 30 mi/h and Peter’s rate is 15 mi/h faster, which is 45 mi/h.

5. More Practice!!! Textbook – p. 108 #10 – 14 even, p. 109 #20 – 26 even. Homework – Worksheet 2.5