Question 1201821
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The inverted parabola equation for the height of the hovercraft is absurd.  With the given equation, the hovercraft...
.. is at its maximum height of 108m at x=3 seconds after takeoff;
.. is at a height of 81m at takeoff and again at x=6 seconds after takeoff;
.. is at height 0 at x=9 seconds after takeoff; and
.. is at a negative height (i.e., below the surface of the water) at all times after x=9 seconds after takeoff<br>
We can of course get an answer to the question that is asked by blindly plugging x=0 in the equation -- but that answer is absurd....<br>