# Is this factoring or something?

• Feb 1st 2010, 06:56 PM
SSK
Is this factoring or something?
I honestly don't know what this is but I think it relates to factoring

I have a problem

9 - [(2-6) + (3-17)]

The answer is 27

But how?
• Feb 1st 2010, 07:00 PM
integral
$9 - [(2-6) + (3-17)]$=
$9-[-4+(-14)]$
$9--18$
$9+18=27$

edit: distributive property :o
• Feb 1st 2010, 07:01 PM
xsavethesporksx
9-[(2-6)+(3-17)]

9-[(-4)+(-14)]

9-[-18]

distribute the negative

9+18 = 27
• Feb 1st 2010, 07:42 PM
Quote:

Originally Posted by SSK
I honestly don't know what this is but I think it relates to factoring

I have a problem

9 - [(2-6) + (3-17)]

The answer is 27

But how?

If you like, you can think in terms of temperature.

If it was $2^o$ and the temperature dropped by $6^o$ then it will have fallen to $-4^o$

If it was $3^o$ and it fell by $17^o$,
it would be $-14^o$

$9-[(2-6)+(3-17)]=9-[-4+-14]$

$-4$ means "subtract" 4
$-4+-14$ means "subtract" 4 and "subtract" 14.
That's subtract 18 altogether.

$9-[-18]$ means "do the opposite" of subtract 18 from 9,
and since subtraction is the opposite of addition,
addition is the opposite of subtraction, then 9--18 is 9+18.

To get the hang of things, you can think that way.
• Feb 1st 2010, 07:54 PM
integral
-- is + because

If you take a positive # c

c

and you subtract a negitive number d

c-(-d)=r

You are taking away a bit less than nothing.
And if you are taking away less than nothing r must be moving further from nothing.

Like owning money.

I owe 5\$ and someone subtracts 4 dollars from my debt, now I owe 1\$
I.E.
-5--4=-1

idk if that helps just trying to put usefull info out there (Thinking)