Question

A hovercraft takes off from a platform.

Its height (in meters),

x

xx seconds after takeoff, is modeled by:

h

(

x

)

=

−

3

(

x

−

3

)

2

+

108

h(x)=−3(x−3)

2

+108h, left parenthesis, x, right parenthesis, equals, minus, 3, left parenthesis, x, minus, 3, right parenthesis, squared, plus, 108

What is the height of the hovercraft at the time of takeoff?

Answer 1

81 meters

Explanation:

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Answer 2

81 meters.

Explanation:

The height (in meters), h(x) of a hovercraft x seconds after takeoff, is modeled by:

`h(x)=-3(x-3)^2+108`

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.

`h(0)=-3(0-3)^2+108\\=-3(-3)^2+108\\=-3(9)+108\\=-27+108\\=81$ meters`

The height of the hovercraft at takeoff is 81 meters.