At the start of the chapter you were given an equation which modelled the leap of

a dolphin as it ‘flew’ out of the water. The equation is h = −0.4d2 + d, where h is

the dolphin’s height above water and d is the horizontal distance from its starting

point. Both h and d are in metres.

1 How high above the water is the dolphin when it has travelled 2 m horizontally

from its starting point?

2 What horizontal distance does the dolphin cover when it first reaches a height of

25 cm?

3 What horizontal distance does the dolphin cover when it next

reaches a height of 25 cm? Explain your answer.

4 What horizontal distance does the dolphin cover in one leap?

(Hint: What is the value of h when the dolphin has completed

its leap?)

5 Can this dolphin reach a height of:

a 0.5 m? b 1 m during a leap?

How can you work this out without actually solving the

equation?

6 Find the greatest height that the dolphin reaches during a leap.

*I REALLY NEED YOUR HELP. ): I DON'T WANNA GET AN E.