Question

Factor the algebraic expression.
18a+15

Answer 1

3(6a + 5)

Explanation:

1) Find the Greatest Common Factor (GCF).

1 - What is the largest number that divides evenly into 18a and 15?

It is 3.

2 - What is the highest degree of a that divides evenly into 18a and 15.

It is 1, since a s not in every term.

3 - Multiplying the results above,

The GCF is 3.

2) Factor out the GCF. (Write the GCF first. Then, in parentheses, divide each term by the GCF.)

3 (18a/3 + 15/3)

3) Simplify each term in parentheses.

3(6a + 5)

Answer 2

Answer: 3(6a+5)

We can confirm this by distributing the 3 back in

3*6a = 18a

3*5 = 15

So 3(6a+5) = 3*6a+3*5 = 18a+15

The process of factoring polynomials like this is basically using the distributive property in reverse.