# Factoring help needed for 49 - (x + 4y)^2

#### texbum

##### New member
I Need Some Help With Factoring. The first problem, in a series of problems I cant get figured out, is:

49-(x+4y)^2

Any help would be much appreciated!

#### Subhotosh Khan

##### Super Moderator
Staff member
Re: I Need Some Help With Factoring

texbum said:
The first problem, in a series of problems I cant get figured out, is:

49-(x+4y)^2

Any help would be much appreciated!
Hint:

49 = $$\displaystyle 7^2$$

and

$$\displaystyle a^2 - b^2 = (a+b)(a-b)$$

#### texbum

##### New member
(7+x-4y)(7-x-4y)?

#### Denis

##### Senior Member
texbum said:
(7+x-4y)(7-x-4y)?
Not quite: (7 + x + 4y)(7 - x - 4y)