The height (in meters) of a shot cannonball follows a trajectory given by $h(t) = -4.9t^2 + 14t - 0.4$ at time t (in seconds). As an improper fraction, for how long is the cannonball at or above a height of 6 meters?

Guest Feb 23, 2019

#1**+1 **

Set h >=6 and solve for t

6>= -4.9 t^2 + 14 t - 0.4

0 >= -4.9 t^2 + 14 t - 6.4 Use Quadratic Formula or graphing to find t = .5714 and 2.286 sec

So between (.5714, 2.286) the cannonball is = to or higher than 6 m

ElectricPavlov Feb 23, 2019