Solve the equation x^2-8x=24 by completing the square

To complete the square, we have to find out what constant number is required to make a perfect square trinomial.we need to divide the coefficient on x, which is -8, by 2, and then square the result. if we do that, we get (-8/2)^2 = (-4)^2 = 16.so we have to add 16 to both sides so that the left hand can be factored as a perfect square trinomial.square root both sides (note that  )so