If using the method of completing the square to solve the quadratic equation x^2+14x-14=0x 2 +14x−14=0, which number would have to be added to "complete the square"?

The area of a square floor on a scale drawing is 64 square centimeters, and the scale drawing is 1 centimeter: 3 ft. what is the area of the actual floor? what is the ratio of the area in the drawing to the actual area? the area of the actual floor is square feet. the ratio of the area in the drawing to the actual area is 1 square centimeter: square feet.