Question 1206396
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Stein Glass, Inc., makes parabolic headlights for a variety of automobiles. 
If one of its headlights has a parabolic surface generated by the parabola x^2 = 12y, 
where should its light bulb be placed? (Hint: Solve the equation for y before you start finding the focus.)
A. 3 units
B. 12 units
C. 4 units
D. 48 units
E. 36 units
F. 2 units
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<pre>
When a parabola is presented by an equation x^2 = ay in this vertex form,

the focus is located at the distance  f = {{{a/4}}} from the vertex.


In this problem, the focus is located at the distance  {{{12/4}}} = 3 units from the vertex.


<U>ANSWER</U>.  Light buble should be placed at 3 units from the vertex.

         Option (A).
</pre>

Solved.