SOLUTION: A water rocket is launched upward with an initial velocity of 48 ft/sec. Its height h, in feet, after t seconds is given by h = 48t - 16t^2. After how many seconds will the height

Question 283805: A water rocket is launched upward with an initial velocity of 48 ft/sec. Its height h, in feet, after t seconds is given by h = 48t - 16t^2. After how many seconds will the height of the rocket be 20 feet? Show all steps necessary to arrive at your solution.
Answer by dabanfield(803) (Show Source): You can put this solution on YOUR website!
A water rocket is launched upward with an initial velocity of 48 ft/sec. Its height h, in feet, after t seconds is given by h = 48t - 16t^2. After how many seconds will the height of the rocket be 20 feet? Show all steps necessary to arrive at your solution.
We need to solve:
20 = 48t - 16t^2
or
16t^2 - 48t + 20 = 0
Divide both sides by 4;
4t^2 - 12t + 5 = 0
(2t - 1)*(2t - 5) = 0
Solutions are:
2t - 1 = 0 and 2t - 5 = 0 or
t = 1/2 and t = 5/2
The first time is on the way up and the second is on the way down.

RELATED QUESTIONS
A water rocket is launched upward with an initial velocity of 48 ft/sec. Its height h, in (answered by scott8148)

A water rocket is launched upward with an initial velocity of 48 ft/sec. It's height h,... (answered by Fombitz)

SOLVING APPLICATIONS Assume that a water rocket is launched upward with initial velocity (answered by Boreal)

Solve using the five-step problem-solving process. Show all steps necessary to arrive at (answered by Alan3354)

Please help with this question. A water rocket is launched upward with an initial... (answered by Fombitz)

A model rocket is launched with an initial velocity of 164 ft/sec. Its... (answered by jorel1380)

Suppose that a bottle rocket is launched upward with a initial velocity of 96ft/sec from... (answered by ikleyn)

Suppose That A Flare Is Launched Upward With An Initial Velocity Of 80 Ft/sec From A... (answered by ankor@dixie-net.com)

The formula gives the height h in feet of an object after t seconds. Here is the... (answered by stanbon)