Question

A water balloon is tossed into the air with an upward velocity of 25ft/s. Its height H(t) in ft after t seconds is given by the function h(t) = - 16t^2 + 25t + 3. Show your work

19. After how many seconds will the balloon hit the ground? (hint: Use the quadratic formula)


20. What will the height be at t = 1 second

Answer 1

19. It notes or hints to using the quadratic formula because the equation can not be solved by factoring alone. Thus you must use the quadratic formula.
A=-16 B=25 C=3
It is so hard to type a normal equation let alone one of the quadratic formula so I will just attach a picture instead.
However you will end up getting two roots/zeros/x-intercepts of -0.11 and 1.67.
However since it is an application question asking for answers only in the first quadrant you must choose the positive x-intercept.
Therefore the water balloon will land at 1.67 seconds.

20. This question is very simple as it asks you to find a height at a given time. You simply put the given time (1second) into the equation and get your answer.
h=-16(1)^2+25(1)+3
h=12

Also don't mind my little scribble there. :)