3. Factor the expression.

d2 + 120 + 36

A (d + 6) 2

B (d - 36) (0 - 1)

OC (d - 6) 2

D (d + 6) (d - 6)

The complete factored form of this equation is (d + 6) ²

Step-by-step explanation:

The first step in factoring this equation is multiply the first term and the last term together. Out first term is d² and our last term is 36. Since d² does not have a coefficient, then we assume this number to be 1.

1 * 36 = 36

So, now we need to find two factors that multiply to 36 and add together to get 12. Two factors that best represents this is 6 and 6. So, we will plug these numbers into our equation. Replace 12d with 6d + 6d.

d² + 6d + 6d + 36

Group the first two terms together and the last two terms together.

(d² + 6d) + (6d + 36)

Now, find the greatest common factor of each parentheses and factor the terms.

d (d + 6) + 6 (d + 6)

From looking at this, we can tell that this equation is a perfect squared equation. So, this means instead of writing both parentheses, we can just write one of the parentheses and square it.

So, the factored form of this equation is (d + 6) ²