Find all real values of $s$ such that $x^2 + sx + 144 - 63 + x^2 - 25 - 18$ is the square of a binomial.
Simplify as
2x^2 + sx + 38
We will have a square of a binomial when the discriminant = 0
s^2 - 4(2)(38) = 0
s^2 = 304
s = ± sqrt [304] = ± 4sqrt (19)
+1557 
