Factor completely x2 - 49

(x + 7)(x - 7)

Explanation: If a variable is taken to an even power, that variable is a perfect square. In this case, x² would therefore be a perfect square.

Since 49 is also a perfect square, what we have here is the difference of two squares. That can be factored as the product of two binomials one with a plus in the middle and one with a minus in the middle.

In the first position will be the factors of x² that are the same.

So we have x and x.

In the second position we will have the

factors of 49 that are the same, 7 and 7.

(x + 7)(x - 7) is your answer which is a factored version of x² - 49.