Solve the problem
-A ball is thrown downward from a window in a tall building. Its position at time $t$ in seconds is $s ( t ) = 16 t ^ { 2 } + 32 t$, where $s ( t )$ is in feet. How long (to the nearest tenth) will it take the ball to fall 140 feet?
A) $1.9 \mathrm { sec }$
B) $4.4 \mathrm { sec }$
C) $2.1 \mathrm { sec }$
D) $3.0 \mathrm { sec }$

Question

Quizplus · Accepted Answer

To find the time it takes for the ball to fall 140 feet, set $s(t) = 140$ and solve for $t$: $16t^2 + 32t = 140$. Simplifying gives $16t^2 + 32t - 140 = 0$. Solving this quadratic equation using the quadratic formula gives $t \approx 2.1$ seconds.

Solve the Problem -A Ball Is Thrown Downward from a Window

Solve the Problem
-A Ball Is Thrown Downward from a Window