# Maths question help anyone

Discussion in 'BlackHat Lounge' started by realdeal85, Jul 23, 2013.

1. ### realdeal85Junior Member

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Hi i have a question its fairly simple but i just cant get my head round it.

I need to multiply out and than simplify the following equation.

a(b-c) +b (c-a)

I have the answer but i need to know how to get to the answer , The answer is = c(b-a)

if any help on how you get that answer will be of great help.

2. ### umerjutt00Jr. VIPJr. VIP

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a(b-c) +b(c-a)

= ab -ac +bc -ba

= ab -ba -ac +bc

= -ac + bc

I think that's the true answer.

3. ### realdeal85Junior Member

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thanks for the reply can you tell me how you got from =ab-ac+bc-ba to = ab-ba-ac+bc to = -ac+bc = c=(b-a)

If you are busy please do not reply i do not want to waste peoples time sir

4. ### umerjutt00Jr. VIPJr. VIP

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=ab -ac +bc -ba

// rearranging

= ab - ba -ac + bc

// ab and ba are equal to each other ab=ba
// so ab - ba =0

= -ac + bc

//taking c as common

= c(-a + b)

//rearranging

5. ### realdeal85Junior Member

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brilliant mate thanks a bunch i wish you all the success in life.

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