SOLUTION: A plastic hoop is thrown upward from the top of a 168 foot high building at a speed of 88 feet per second. The plastic hoop's height above ground can be modeled by the equation Hbr

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: A plastic hoop is thrown upward from the top of a 168 foot high building at a speed of 88 feet per second. The plastic hoop's height above ground can be modeled by the equation Hbr      Log On


   

Question 1138933: A plastic hoop is thrown upward from the top of a 168 foot high building at a speed of 88 feet per second. The plastic hoop's height above ground can be modeled by the equation Hbracket(t)=-16sup(t,2)+88t+168.
When does the plastic hoop reach the maximum height?
t= seconds
Found 2 solutions by josgarithmetic, ikleyn:
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Hbracket(t)=-16sup(t,2)+88t+168.
?


Maybe more like H(t)=-16t^2+88t+168
?

-32t%2B88=0
88=32t
22=8t
11=4t
t=11%2F4
t=2%263%2F4seconds

Answer by ikleyn(52778) About Me  (Show Source):
You can put this solution on YOUR website!
.

The correct answer is  t = 23%2F4 seconds.