Question

An object is dropped from a bridge and allowed to freefall to the ground. The height of the object over time can be modeled using h(t) = 144 – 16t2.

Answer 1

Answer:

3 seconds

Step-by-step explanation:

Complete question:

An object is dropped from a bridge and allowed to freefall to the ground. The height of the object over time can be modeled using h(t)=144-16t2. How many seconds will it take the object to reach the ground? 2 seconds 3 seconds 9 seconds 16 seconds

Given the height of an object modelled by the expression;

h(t)=144-16t²

The object will reach the ground when h(t) = 0

Substitute into the formula

0 = 144 - 16t²

-144 = -16t²

144 = 16t²

Swap

16t² = 144

t² = 144/16

t² = 9

Square root both sides

√t² = ±√9

t = ±3secs

Since the time cannot be negative, hence the object will reach the ground 3 seconds after