# Math Help - [SOLVED] Here I am stuck again this time on factoring

1. ## [SOLVED] Here I am stuck again this time on factoring

(a+b)^2 - 100

-> (a+b)(a+b)-100
-> a^2+2ab+b-100
-> a(a+2b)(b^2-100)
-> a(a+2b)(b -10)(b+10)

The answer in the book (a+b-10)(a+b+10)

And I have not a clue on how they got this ? any help would be appreciated

2. The difference of 2 squares says

$x^2-y^2 = (x-y)(x+y)$

Originally Posted by onymousillusion
(a+b)^2 - 100
$(a+b)^2 - 100$

$(a+b)^2 - 10^2$

$(a+b-10)(a+b+10)$

3. Thank you... I see it now...