Final answer:
The height of the hovercraft at the time of takeoff is -33 units.
Step-by-step explanation:
The height of the hovercraft at the time of takeoff can be found by evaluating the function h(x) = - (x-11)(x+3) at x = 0, which represents the time of takeoff. To find the height, substitute x = 0 into the function:
h(0) = - (0-11)(0+3) = - (11)(3) = -33
Therefore, the height of the hovercraft at the time of takeoff is -33 units.