How do I factor ac-bc+ad-bd

Question

parthkohli · Answer

Factor the first two terms, and then the last two.

anonymous · Answer

How would I do that

parthkohli · Answer

Can you factor $ac -bc$?

anonymous · Answer

I do not know how to factor

hero · Answer

`(ac-bc)` + `(ad-bd)` 

Hint: notice that 
c is common to the first two terms
d is common to the last two terms

Factor out what is common

anonymous · Answer

So how would i factor?  is it ab + a - b

hero · Answer

Correctly factoring as I suggested would lead to this:

`c(a - b)` + `d(a - b)`

Unfortunately, we are not done because now a - b is common to both so we have to factor that out as well. Any idea how?

anonymous · Answer

ca - cb + da - db ?

hero · Answer

That would be distribution, not factoring

anonymous · Answer

I dont know how to factor. can you explain

hero · Answer

1. Given:
    ac-bc+ad-bd 

2. Place parentheses around first two terms and last two terms:
    (ac - bc) + (ad - bd)

3. Factor c out of the first two terms; Factor d from the last two terms:
    c(a - b) + d(a - b)

4. Notice that now (a - b) is common to both terms, so factor that out to get:
    (a - b)(c + d)

anonymous · Answer

thank you!

hero · Answer

So this means you should understand how to do similar problems.