If a projectile is launched upward from a height of 96 feet at an initial velocity of 80 feet per second, then its height $h$ after $t$ seconds is given by the function $h(t)=-16 t^{2}+80 t+96$. After how many seconds does the projectile land on the ground?
A) 6 seconds
B) 11 seconds
C) 3.0 seconds
D) 5.0 seoonds

Question

Quizplus · Accepted Answer

To find when the projectile lands on the ground, we set $h(t) = 0$ and solve for $t$. Substituting the given function, we get $0 = -16t^2 + 80t + 96$. Solving this quadratic equation, we find that $t = 6$ seconds is the positive solution that represents the time when the projectile lands on the ground.

If a Projectile Is Launched Upward from a Height of 96