Question

The equation y = (-16t-2)(t-1) represents the height in feet of a beach ball thrown by a child as a function of time, t ,in seconds.
1. Find the zeros of the function. Explain or show your reasoning.

2. What do the zeros tell us in this situation? Are both zeros meaningful?

Answer 1

Answer:

y = (-16t-2)(t-1)

To find the zeros, let's set y = 0 and separate these two expressions in parenthesis with the zero product property.

0 = -16t-2

0 = t-1

Now let's solve for t and get two zeros.

0 = -16t-2

2 = -16t

t = -1/8

0 = t-1

t = 1

1. Our two zeros are t = -1/8 and t = 1.

2. The two zeros are not both meaningful! Remember that this is modeling time, and we don't really care about -1/8 seconds. We don't need that negative time measurement, so we just want to know what's happening at 1 second. And at one second, the ball is on the ground. Great, so we know that height of ball = 0 after 1 second.