Complete the square: x^2 + 16x + ___

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

The interior angles formed by the side of a hexagon have measures of them up to 720° what is the measure of angle a

Varies inversely with x. if y=8.5 when x=-1 find x when y=-1