13
if the equation y = (x - 6)(x + 12) is graphed in the
xy-plane, what is the x-coordinate of the parabola's
vertex?
a)-6
b)-3
c)3
d)6
-6
-3
3
6.

Apinhole camera is made out of a light-tight box with a piece of film attached to one side and pinhole on the opposite side. the optimum diameter d(in millimeters) of the pinhole can be modeled by d=1.9[ (5.5 x 10^-4) l) ] ^1/2, where l is the length of the camera box (in millimeters). what is the optimum diameter for a pinhole camera if the camera box has a length of 10 centimeters