Question

The path of a firework is described by the function:

h(t) = -4.9(t-5)² + 124 where h(t) is the height of the firework, in meters, and t is the time in
seconds, since the launch.
What is the vertex of the function, and what does it mean in context?
A. (5, 4.9); At 5 seconds, the firework is 4.9 meters above the ground.
B. (124, 5); At 124 seconds, the firework is 5 meters above the ground.
C. (4.9, 124); At 4.9 seconds, the firework is 124 meters above the ground.
D. (5, 124); At 5 seconds, the firework is 124 meters above the ground.

Answer 1

D

Explanation:

Because this binary function opens down, and it has an extreme point, at t=5, and you plug it in and you get 124 as the maximum.