Maths question help anyone

R

realdeal85

Junior Member

Feb 25, 2013

170

12

• Jul 23, 2013

• #1

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.

 

umerjutt00

Elite Member

Oct 28, 2011

4,373

2,493

• Jul 23, 2013

• #2

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

= ab -ac +bc -ba

= ab -ba -ac +bc

= -ac + bc

= c (b-a) [Answer]

I think that's the true answer.

 

R

realdeal85

Junior Member

Feb 25, 2013

170

12

• Jul 23, 2013
• Thread Starter Thread Starter

• #3

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

 

umerjutt00

Elite Member

Oct 28, 2011

4,373

2,493

• Jul 23, 2013

• #4

=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

= c(b - a) [ANswer]

 

R

realdeal85

Junior Member

Feb 25, 2013

170

12

• Jul 23, 2013
• Thread Starter Thread Starter

• #5

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

 

umerjutt00

Elite Member

Oct 28, 2011

4,373

2,493

• Jul 23, 2013

• #6

realdeal85 said:

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

Click to expand...

In which grade are you?

 

gregevskye

BANNED

Jul 15, 2013

308

37

• Jul 23, 2013

• #7

Your are brilliant in Mathematics and your also insert the comment there that will help to everyone to understand it easily. You did a great job Good luck.

 

3eester

Senior Member

Jr. VIP

Jun 28, 2013

987

71

• Jul 24, 2013

• #8

c(b-a) is the right answer