you spend 5 hrs. first you have to substract 45 from 120 because it is a default charge. 120-45 = 75. if you divide 75 by 15 you get 5 hrs. because it 15$ per hour.

7 0

2 years ago

The height of a ball (in feet) after t seconds is given by the quadratic function h=-16(t-5)^2+116

Dmitriy789 [7]

Check the picture below, so pretty much reaches its maximum height at the vertex, now let's take a peek at the equation above hmmmm

$~~~~~~\textit{vertical parabola vertex form} \\\\ y=a(x- h)^2+ k\qquad \begin{cases} \stackrel{vertex}{(h,k)}\\\\ \stackrel{"a"~is~negative}{op ens~\cap}\qquad \stackrel{"a"~is~positive}{op ens~\cup} \end{cases} \\\\[-0.35em] ~\dotfill\\\\ h(t)=-16(t ~~ - ~~ \stackrel{h}{5})^2~~ + ~~\stackrel{k}{116}~\hfill \underset{maximum~height}{\stackrel{vertex}{(5~~,~~\underset{\uparrow }{116})}}$