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(electricity) How do I solve for A,B,C when: (1)-2A+B-3C=-9 (2)2A      -C=-1 (3)A- B...

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t4trendesetter | (Level 1) Honors

Posted July 8, 2013 at 7:29 AM via web

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(electricity)

How do I solve for A,B,C when:

(1)-2A+B-3C=-9

(2)2A      -C=-1

(3)A- B + 4C =11

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aruv | High School Teacher | (Level 2) Valedictorian

Posted July 8, 2013 at 7:54 AM (Answer #1)

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We have

`-2A+B-3C=-9`                 (i)

`2A-C=-1`                                (ii)

`A-B+4C=11`                         (iii)

adding (i) and (ii),we have

`B-4C=-10`                             (iv)

adding 2times (iii) to (i),we have

`-B+5C=13`                             (v)

adding (iv) and (v) ,we have

`C=3`

substitute C=3 in  9iv) we have

B-12=-10

B=-10+12

B=2

substitute C=3  in (ii)

2A-3=-1

2A=-1+3

2A=2

A=1

Thus answer is

A=1, B=2, and C=3.

 

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