1. Pamela Leutwyler

2. A B Town A is exactly 100 miles from Town B

3. A B At noon train A leaves town A and travels toward town B at a rate of 20 mph

4. A B Town A is exactly 100 miles from Town B At noon train A leaves town A and travels toward town B at a rate of 20 mph At 1PM train B leaves town B and travels toward town A at a rate of 60 mph

5. Let’s replay the motion from the beginning

6. A B Town A is exactly 100 miles from Town B At noon train A leaves town A and travels toward town B at a rate of 20 mph

7. A B Town A is exactly 100 miles from Town B At noon train A leaves town A and travels toward town B at a rate of 20 mph At 1PM train B leaves town B and travels toward town A at a rate of 60 mph

8. A B Town A is exactly 100 miles from Town B At noon train A leaves town A and travels toward town B at a rate of 20 mph At 1PM train B leaves town B and travels toward town A at a rate of 60 mph At what time do the trains meet?

9. A B Town A is exactly 100 miles from Town B At noon train A leaves town A and travels toward town B at a rate of 20 mph At 1PM train B leaves town B and travels toward town A at a rate of 60 mph At what time do the trains meet? distanceratetime (# units of time) train A train B

10. A B Town A is exactly 100 miles from Town B At noon train A leaves town A and travels toward town B at a rate of 20 mph At 1PM train B leaves town B and travels toward town A at a rate of 60 mph At what time do the trains meet? distanceratetime (# units of time) 20 60 train A train B fill in the information that is explicitly stated

11. A B Town A is exactly 100 miles from Town B At noon train A leaves town A and travels toward town B at a rate of 20 mph At 1PM train B leaves town B and travels toward town A at a rate of 60 mph At what time do the trains meet? distanceratetime (# units of time) 20x 60 train A train B Let x represent the number of hours that train A travels

12. A B Town A is exactly 100 miles from Town B At noon train A leaves town A and travels toward town B at a rate of 20 mph At 1PM train B leaves town B and travels toward town A at a rate of 60 mph At what time do the trains meet? distanceratetime (# units of time) 20x 60x - 1 train A train B Let x represent the number of hours that train A travels train B starts 1 hour later than train A if A travels for x hours then B travels for x - 1 hours

13. A B Town A is exactly 100 miles from Town B At noon train A leaves town A and travels toward town B at a rate of 20 mph At 1PM train B leaves town B and travels toward town A at a rate of 60 mph At what time do the trains meet? distanceratetime (# units of time) 20x 60x - 1 train A train B

14. A B Town A is exactly 100 miles from Town B At noon train A leaves town A and travels toward town B at a rate of 20 mph At 1PM train B leaves town B and travels toward town A at a rate of 60 mph At what time do the trains meet? distanceratetime (# units of time) 20x 60x - 1 train A train B formula: distance = (rate) x (time)

15. A B Town A is exactly 100 miles from Town B At noon train A leaves town A and travels toward town B at a rate of 20 mph At 1PM train B leaves town B and travels toward town A at a rate of 60 mph At what time do the trains meet? distanceratetime (# units of time) 20x20x 60(x – 1)60x - 1 train A train B formula: distance = (rate) x (time)

16. A B Town A is exactly 100 miles from Town B At noon train A leaves town A and travels toward town B at a rate of 20 mph At 1PM train B leaves town B and travels toward town A at a rate of 60 mph At what time do the trains meet? distanceratetime (# units of time) 20x20x 60(x – 1)60x - 1 train A train B distance traveled by train Adistance traveled by train B

17. A B Town A is exactly 100 miles from Town B At noon train A leaves town A and travels toward town B at a rate of 20 mph At 1PM train B leaves town B and travels toward town A at a rate of 60 mph At what time do the trains meet? distanceratetime (# units of time) 20x20x 60(x – 1)60x - 1 train A train B distance traveled by train Adistance traveled by train B += 100

18. A B Town A is exactly 100 miles from Town B At noon train A leaves town A and travels toward town B at a rate of 20 mph At 1PM train B leaves town B and travels toward town A at a rate of 60 mph At what time do the trains meet? distanceratetime (# units of time) 20x20x 60(x – 1)60x - 1 train A train B distance traveled by train Adistance traveled by train B += 100 20x60(x – 1 )

19. A B Town A is exactly 100 miles from Town B At what time do the trains meet? distanceratetime (# units of time) 20x20x 60(x – 1)60x - 1 train A train B distance traveled by train Adistance traveled by train B += 100 20x60(x – 1 ) 20x + 60 ( x - 1 ) = 100 20x + 60x - 60 = 100 80x = 160 x = 2 train A starts at noon and travels for 2 hours before meeting train B 2 PM