The expression (x² + 13x + 30) can be factored as ((x + a)(x + b)), and the expression (x² + 5x - 50) can be factored as ((x + b)(x - c)), where (a), (b), and (c) are integers. What is the value of (a + b + c)?
a) (18)
b) (20)
c) (22)
d) (24)