Help? I tried the first two, can't get them. I don't know how I got the third.

Answer:
See below
Step-by-step explanation:
(6x+14)(x-8) = Expand
6x^2 - 48x + 14x - 112 =
6x^2 - 34x-112 A = 6 B = -34
Answer:
Step-by-step explanation:
[tex]x(6x+14)-8(6x+14)\\6x^2+14x-48x-112\\[/tex]
Rest, you have to substitute the value. Such as A= -112