1. 2003
The Olympic Dream

5. 1 3

9. Question 2

10. When t = 30
C = = 170

11. Which ONE of the three phone cards has the highest connection fee per call?

12. Keep in touch card

13. How is this shown by the graphs?

14. Highest point on Cost axis (highest y intercept) - 40 c

15. How long is a call that costs the same using the No Frills card and the Keep in Touch card?

16. 20 minutes

17. How is this shown by the graph?

18. The intersection of the two lines.

19. Use the graph to write the equation for the No Frills card.

21. Use the graph to write the equation for the Keep in Touch card.

23. Question 3

29. Write the equation for h, the height above the water, in terms of time, t, that models Wendy’s dive until she touches the bottom of the pool.
The graph is upside down and moved ‘0.5’ in the x direction. It goes through the points (0, 4) and (2, 0)

30. Equation is using symmetry
The graph is upside down and moved ‘0.5’ in the x direction. It goes through the points (0, 4) and (2, 0)

31. Because the y-intercept is 4, the equation is
The graph is upside down and moved ‘0.5’ in the x direction. It goes through the points (0, 4) and (2, 0)

32. Write an equation that models her return from the bottom of the pool back to the surface. You may wish to draw on the graph above.

33. The line goes through the point (7, 0) so
0 = 2 x 7 + c  c = -14

34. (a) Wendy knows that to achieve a perfect dive, her hands must be within 4 metres of the bottom of the pool 2.5 seconds after starting her dive.

35. (a). First we need to know where she is at 2. 5 secs
(a) First we need to know where she is at 2.5 secs. Substitute into the equation.

36. Next we need to know where the bottom of the pool is by finding where the two graphs meet.

38. The graphs meet at -8 so the pool is 8 m deep.