Krzysztof solved the quadratic equation 11x^2+44x-99=0 by completing the square. In the process, he came up with the equivalent equation (x+r)^2 = s,where r and s are constants.What is r+s.
11x^2 + 44x - 99 = 0 divide through by 11
x^2 + 4x - 9 = 0 add 9 to both sides
x^2 + 4x = 9 take 1/2 of 4 = 2.....square this = 4 add to both sides
x^2 + 4x + 4 = 9 + 4 factor the left side, simplify the right
(x + 2)^2 = 13
r = 2 s = 13
r + s = 15
