The expression $x^2 + 13x + 30$ can be written as $(x + a)(x + b),$ and the expression $x^2 + 5x - 50$ written as $(x + b)(x - c)$, where $a$, $b$, and $c$ are integers. What is the value of $a + b + c$?
I think the answer is 8
(x+3)(x+10) and (x+10)(x-5)
a=3
b=10
c=-5
