An umbrella sprinkler is positioned on a ceiling at a point whose x- coordinate is 0. Negative values of a indicate distances, in meters, to the left of the position of the sprinkler, and positive values indicate distances to the right. The path of water from the sprinkler can be modeled by the quadratic function

w(x) = -1/4(x^2 -12 ) where w(x) is the height of the water, in meters, at position x.

Required:
Which equivalent expressions displays the height of the ceiling as a constant or coefficient?