Question

A hovercraft takes off from a platform. It's height (in meters), x seconds after takeoff, is modeled by h(x)=-(x-11)(x+3) How many seconds after takeoff will the hovercraft land on the ground?

Answer 1

11seconds

Explanation:

Given the height of the hovercraft expressed as;

(x)=-(x-11)(x+3)

The height of the hovercraft on the ground is 0, hence;

0 =-(x-11)(x+3)

-(x-11)(x+3) = 0

Multiply both sides by minus

(x-11)(x+3) = 0

x-11 = 0 and x+3=0

x = 11 and -3

Since time cannot be negative, hence the hovercraft will land after 11seconds