Factoring Polynomials Help Please!?!?

Question

1.) 6x^2 - 13x - 5

(3x + 1)(2x - 5)

2.) 2x^2 + 15x + 7

(2x + 14)(2x - 1)

Can someone help me understand why these are diferent? why on the second one must i add the two "product" and "sum" to equal the middle

while the other one (1) only equals to "-5"

thanks

Answer 1

Your factoring for the second problem isn't correct. It should be
(2x + 1)(x + 7)

I'm not clear on what your question is. Could you explain it further, or give an example?