Luca is in a culvert below street level. He launches an object at an upward velocity of 40 feet per second. Use GeoGebra to graph the situation using the formula y=−16t2+40t−5

. How far above or below street level is Luca’s initial launching point?(1 point)
Responses

5 feet above
5 feet above

0 feet above or below
0 feet above or below

5 feet below
5 feet below

2.5 feet below

1 answer

To determine how far above or below street level Luca's initial launching point is, we can analyze the equation given:

\[ y = -16t^2 + 40t - 5 \]

In this equation, \( y \) represents the height of the object (in feet) as a function of time \( t \) (in seconds). The constant term, -5, indicates the initial height of the object at \( t = 0 \).

When \( t = 0 \):

\[ y(0) = -16(0)^2 + 40(0) - 5 = -5 \]

This means that the initial height of the launching point is \( -5 \) feet. Since this value is negative, it indicates that Luca's launching point is 5 feet below street level.

Thus, the correct response is:

5 feet below.