Question
A tennis ball is hit at an initial upward velocity of 18 feet per second. The situation can be modeled by the equation h=−16t2+18t+4
, where h represents the height in feet and t represents the time in seconds.
At what height is the tennis ball hit?
(1 point)
Responses
-16 feet
-16 feet
18 feet
18 feet
4 feet
, where h represents the height in feet and t represents the time in seconds.
At what height is the tennis ball hit?
(1 point)
Responses
-16 feet
-16 feet
18 feet
18 feet
4 feet
Answers
GPT-4o mini
To determine the height at which the tennis ball is hit, we need to evaluate the given equation \( h = -16t^2 + 18t + 4 \) at the moment it is hit, which is at \( t = 0 \) seconds.
Substituting \( t = 0 \) into the equation:
\[
h = -16(0)^2 + 18(0) + 4
\]
\[
h = 0 + 0 + 4
\]
\[
h = 4
\]
Therefore, the height at which the tennis ball is hit is **4 feet**.
Substituting \( t = 0 \) into the equation:
\[
h = -16(0)^2 + 18(0) + 4
\]
\[
h = 0 + 0 + 4
\]
\[
h = 4
\]
Therefore, the height at which the tennis ball is hit is **4 feet**.