Answer:
Focus of a Parabola. A parabola is set of all points in a plane which are an equal distance away from a given point and given line. The point is called the focus of the parabola and the line is called the directrix. The focus lies on the axis of symmetry of the parabola.
Step-by-step explanation:
AC
Same line segment just goes in the other direction.
Um.. I can't sketch a graph on here.
A discrete function can't be an absolute value function because an absolute value function is continuous. But, the function equation can be as simple as
f(x) = - | x + 1 |
Just don't connect the dots when you draw it and boom, you're done.
Answer:
The after 9/4 seconds the football is at its highest point which is 81 feet if Lillian kicks a football. Its height in feet is given by h(t)= -16t²+72t
<h3>What is a parabola?</h3>
It is defined as the graph of a quadratic function that has something bowl-shaped.

Making perfect square:
![\rm h(t)= -[(4t)^2-72t+9^2 -9^2]](https://tex.z-dn.net/?f=%5Crm%20%20h%28t%29%3D%20-%5B%284t%29%5E2-72t%2B9%5E2%20-9%5E2%5D)
![\rm h(t)= -[(4t-9)^2 -81]](https://tex.z-dn.net/?f=%5Crm%20%20h%28t%29%3D%20-%5B%284t-9%29%5E2%20-81%5D)

The highest point will be when term (4t-9)² becomes zero
So the highest point = 81 feet, and it takes:
t = 9/4 seconds
Thus, the after 9/4 seconds the football is at its highest point which is 81 feet if Lillian kicks a football. Its height in feet is given by h(t)= -16t²+72t
Learn more about the parabola here:
brainly.com/question/8708520
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