How do you factorize quadnomials

Could someone please explain how to factorize quadnomials? Here are my first 2 questions out of 8:
1) 2x + 8 + bx+ 4b
2) x^2 + 5x + 2x + 10

1) 2x + 8 + bx + 4b
2(x+4) + b(x+4)
See a factor from the first two terms? Factor it out! What about the last two terms? Factor it out!
(2+b)(x+4)

2)x^2 + 5x + 2x + 10
The 5x and the 2x can be just 7x.
x^2 + 7x + 10
(x+5)(x+2)
If you know how to factorize trinomials, just do that. Or do this:
x^2 + 5x + 2x + 10
x(x+5) + 2(x+5)
(x+2)(x+5)
Either way, same answer.

1]
rearrange into groups

2x + bx + 8 + 4b

x[2 + b] + 4[2 + b]
[2+b] is a common factor
leaves

[2+b][x+4]

2]
do the same type of grouping
put 5x with 10
and 2x with x^2

x^2 + 2x + 5x + 10
x[x+2] + 5[x+2]
[x+2] is a common factor
leaves

[x+2][x+5]

(2+b)(x+4)
(x+5)(x+2)