Question

(1 point) A coin, thrown upward at time t = 0 from an office in the Empire State Building, has height in feet above the ground t

Answer 1

Answer:

The coin was thrown from 448 feet

Time to hit the ground is 7 seconds

Step-by-step explanation:

Given

$h(t) = -16(t - 7)(t + 4)$

Solving (a): Height when coin is thrown

At this point t = 0

So, we have:

$h(0) = -16(0 - 7)(0 + 4)$

Solve expressions in the brackets

$h(0) = -16(-7)(4)$

$h(0) = 448$

Hence, the coin was thrown from 448 feet

Solving (b): Time to hit the ground

At this point, h = 0.

So, we have:

$0 = -16(t - 7)(t + 4)$

Reorder

$-16(t - 7)(t + 4) = 0$

Divide both sides by -16

$(t - 7)(t + 4) = 0$

This gives:

$t - 7 = 0$      or      $t + 4 = 0$

$t = 7$   or     $t = -4$

Since, time can't be negative;

$Time = 7\ seconds$