How do you factor completely 6a^2-15a-8a+20?

1 Answer
Nov 12, 2015

(3a - 4)(2a - 5) = 0.
a = 4/3.
a = 5/2.

Explanation:

We start with 6a^2 - 15a - 8a +20.
First of all, we see we can do 15 - 8a easily, so
-15 - 8a turns into -23a. So,
we have 6a^2 - 23a + 20.

Now, we multiply the factor of 6a^2, (6) by the last number (20). We get 120. We now look for factors that add up to 23.
For example, -8 and -15 add up to 23, and multiplied, give 120.

We now put out the equation as:
((6a - 8)(6a - 15))/6. We now divide the right bracket and the denominator by 3, to simplify it. We get:
((6a - 8)(2a - 5))/2. We now divide the left bracket and the denominator by 2, leaving the denominator as 1. We get:
(3a - 4)(2a - 5).

Hope it Helps! :D .