NEED HELP ASAP 15POINTS! Factor k^2 - 81.
(k + 9)(k + 9)
(k - 9)(k - 9)
(k - 9)(k + 9)

(k +9)(k - 9)

Step-by-step explanation:

a² - b² = (a + b)(a -b)

k² - 81 = k² - 9²

           = (k +9)(k - 9)

The answer is:

(Option 1).

(Option 4).

(Option 5).

The explanation for this answer is shown below:

1. The commutative property of addtion establishes that if you change the order of the addends, the sum will not change.

2. Let's say that and are real numbers, Then they can added them to obtain a result :

3. If you change the order, you will obtain the same result:

4. Therefore, the only options that show the applicaction of this property, are the options shown above.