How is completing the square beneficial?

The area of a rectangle is 10 cm^2. one side of the rectangle is x cm. express the perimeter of the rectangle in terms of x and show that this rectangle cannot have a perimeter of 12 cm. the perimeter of the rectangle in terms of x is __ cm

Find the amplitude of a sinusoidal function that models this temperature variation

240 seventh graders and two-thirds of the students participate in after-school activities how many students participate in after-school activities