Name Alg1 Q3 Quiz 1 Review January 22, 2008 d = rt and Substitution Part I: Solve each using d = rt and state your answer in hours and minutes (unless it asks for exact time): 1) Two trains leave the station at the same time. One is traveling east at a rate of 68 mph. The other is traveling west at a rate of 57 mph. How long to they have to travel until they are 606.25 miles apart? 2) Two trains leave the station at the same time. One is traveling east at a rate of 63 mph. The other is traveling east at a rate of 91 mph. How long to they have to travel until they are 103.6 miles apart? 3) Two trains leave the station at the 2:30 pm. One is traveling east at a speed of 78 mph. The other is traveling west at 65 mph. At what time will they be 867.15 miles apart? 4) Two buses leave the station at 10:15 am. One is traveling north at a speed of 74 mph. The other is traveling north at 59 mph. At what time will they be at 72 miles apart? 5) Two trains leave the station at the 1:50 am. One is traveling east at a rate of 89 mph. The other is traveling west at a rate of 72 mph. How long to they have to travel until they are 853.3 miles apart? 6) Two planes leave the airport at 11:40 am. One is traveling south at a speed of 268 mph. The other is traveling south at 243 mph. At what time will they be 216.25 miles apart? Part II: Solve each system algebraically and check: 1) x = 6y - 7 2) y = 9 + 4x 9x – 8y = 75 6x - 7y = 47 4) y =9x + 44 8x - 11y = 62 7) x + 7y = 2 8x + 5y = 118 3) -x = 15 – 4y 8x + 7y = -42 5) 7x + 12y = -39 x – 6y= - 21 6) 7x + y = 12 8x – 11y = 38 8) 6x + 11y = 24 -y = 8x + 9 9) x – 2y= 25 7x + 8y = -34 Answer Key: Part I: 1) 4h 51m 4) (t= 4h 48m) 3:03 2) 3h 42m 5) (t= 5h 18m) 7:08 3) (t= 6h 9m) 8:39 6) (t= 8h 39m) 8:19 Part I: 1) (11,3) 4) (-6,-10) 7) (16,-2) 2) (-5,-11) 5) (-9,-2) 8) (-1.5,3) 3) (-7,2) 6) (2,-2) 9) (6,-9.5)