For what real values of $s$ is $x^2 + sx + 144$ the square of a binomial?
x2 + sx + 144 = (s + 12)(s + 12) = (s + 12)2 = s2 + 24x + 144 ---> s = 24
CPhill has pointed out to me that we also need -24 as an answer.
Thanks, CPhill!
