Answer:
81 meters.
Step-by-step explanation:
The height (in meters), h(x) of a hovercraft x seconds after takeoff, is modeled by:
We are to determine its height at the time of takeoff.
Now, at the time of takeoff, x=0.
We substitute x=0 to solve for h.
The height of the hovercraft at takeoff is 81 meters.
Consider all parabolas:
1.
When x=-3, y=-1, then the point (-3,-1) is vertex of this first parabola.
2.
When x=-4, y=-4, then the point (-4,-4) is vertex of this second parabola.
3.
When x=2.5, y=20.25, then the point (2.5,20.25) is vertex of this third parabola.
4.
When x=3.5, y=19.25, then the point (3.5,19.25) is vertex of this fourth parabola.
5.
When x=-1.75, y=-1.125, then the point (-1.75,-1.125) is vertex of this fifth parabola.
6.
When x=2, y=13, then the point (2,13) is vertex of this sixth parabola.