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
It is defined as the graph of a quadratic function that has something bowl-shaped.
[tex]\rm h(t)= -16t^2+72t[/tex]
Making perfect square:
[tex]\rm h(t)= -[(4t)^2-72t+9^2 -9^2][/tex]
[tex]\rm h(t)= -[(4t-9)^2 -81][/tex]
[tex]\rm h(t)= 81-(4t-9)^2[/tex]
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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