Answered

IDNLearn.com is your reliable source for expert answers and community insights. Get the information you need from our experts, who provide reliable and detailed answers to all your questions.

x2 - x - 6 =
Simplified. I know the answer is (x+2)(x-3), but I don't understand how the answer was achieved. Can I please get an explanation of this?

Sagot :

[tex]x^2-x-6=(x+2)(x-3)\\\\-x=2x-3x\\-6=2\times(-3)\\\\or\\\\x^2-x-6=x^2+2x-3x-6=x(x+2)-3(x+2)=(x+2)(x-3)[/tex]
AL2006idn
I had a lot of trouble with this when my algebra class started doing it,
a long time ago.

The key is this:  Look at the -6 at the end.  You have to find two factors
of that number that add up to the -1 in the middle.

Here are the possible factors of -6 :

-1 ... 6
+1 ... -6
-2 ... 3
+2 ... -3

Can you find a pair on the list that adds up to -1 ? 
How about +2 and -3 ?
Their product is -6 and their sum is -1.  That's what you need.

Now set up a couple of binomial factors like this:  (x....) (x....)
and write in the pair of numbers you found:  (x + 2) (x - 3)
That's the factored form of the original expression.


We value your participation in this forum. Keep exploring, asking questions, and sharing your insights with the community. Together, we can find the best solutions. IDNLearn.com provides the best answers to your questions. Thank you for visiting, and come back soon for more helpful information.