Solve the problem.
-A coin is tossed upward from a balcony $252 \mathrm{ft}$ high with an initial velocity of $16 \mathrm{ft} / \mathrm{sec}$. During what interval of time will the coin be at a height of at least $60 \mathrm{ft}$ ? $\left(\mathrm{h}=-16 \mathrm{t}^{2}+\mathrm{v}_{0} \mathrm{t}+\mathrm{h}_{0}\right.$. $)$
A) $0 \leq \mathrm{t} \leq 1$
B) $4 \leq \mathrm{t} \leq 8$
C) $0 \leq \mathrm{t} \leq 4$
D) $3 \leq \mathrm{t} \leq 4$

Question

Quizplus · Accepted Answer

The coin will be at a height of at least $60 \mathrm{ft}$ when $h(t) \geq 60$. So, we solve the inequality $-16 t^{2}+16 t+252 \geq 60$. Simplifying, we get $-16 t^{2}+16 t+192 \geq 0$. Factoring, we get $-8(2 t+12)(t-2) \geq 0$. So, the coin will be at a height of at least $60 \mathrm{ft}$ when $0 \leq t \leq 4$.

Solve the Problem 252ft252 \mathrm{ft}252ft High with an Initial Velocity Of 16ft/sec16 \mathrm{ft} / \mathrm{sec}16ft/sec

Solve the Problem $252 \mathrm{ft}$ High with an Initial Velocity Of $16 \mathrm{ft} / \mathrm{sec}$