1. ## Writing Equations - Quadratics 3

Ted popped a baseball straight up with an initial upward velocity of 48 ft/s. The height, h, in feet, of the ball above the ground is modeled by the function h(t) = 3 + 48t - 16t^2. How long was the ball in the air if the catcher catches the ball 3 ft above the ground? Is your answer reasonable?

My attempt:

h(t) = 3 + 48t - 16t^2

3(t) = 3 + 48t - 16t^2

This is how much I have done, I'm not sure if I did that right, I think I need to isolate t, but I do not know how to do that algebraically.

2. ## Re: Writing Equations - Quadratics 3

You want to set $h(t)=3$, then take the root such that $t\ne0$. You would have:

$3=3+48t-16t^2$

Subtract 3 from both sides, factor out 16t, and equate the other factor to zero to find the root you want. What do you find?