You put the highest exponent power first, then you go down until you reach a regular number (a number with a variable goes before a normal number)
Ex: 5x^3+2x^2+4x+5
Divide the distance by the time and you will get your answer
V(cylinder)= πr²h
d=2r,
d is diameter, r is radius.
When diameter is tripled, a new diameter D=3d,
new radius R=3d/2=(3*2r)/2=3r
R=3r
V(new cylinder)= πR²h = π(3r)²h=9πr²h
V(new cylinder)/V(cylinder)=9πr²h/πr²h=9
Volume new cylinder 9 times more the volume of old cylinder.
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
#SPJ1
18/3=6
6x2=12
She can get 12 books from the store