Answer:
(8) The horizontal distance is 20 meters
(9) Maximum height is 2.5 meters
(c) The height when the horizontal distance is 7 meters is 2.275 meters
Explanation:
Given

Solving (8): The horizontal distance which the ball lands
When the ball lands, the height is at 0.
So, we have:


Rewrite as:

Factorize

Split

Solve for d

or

---- This represents the starting point
---- This represents the horizontal distance traveled
Solving (9): Maximum height
The maximum of a quadratic equation
is:

So:
means that:

The maximum is:





Substitute
in
to calculate the maximum height



Solving (10): The height when the horizontal distance is 7m
Substitute
in



