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12-23c=7(9-c)

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schooledmom | Salutatorian

Posted January 3, 2013 at 12:02 AM via web

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12-23c=7(9-c)

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ncchemist | eNotes Employee

Posted January 3, 2013 at 12:11 AM (Answer #1)

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I assume you want to solve the above equation for c.  See the work below:

12-23c=7(9-c)      multiply the seven out on the right side:

12-23c=63-7c      add 23c to both sides to isolate the variable:

12=63-7c+23c=63+16c    subtract 63 from both sides:

12-63=-51=16c     divide both sides by 16:

c=-51/16=-3.1875

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embizze | High School Teacher | (Level 1) Educator Emeritus

Posted August 8, 2013 at 8:22 PM (Answer #1)

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Solve 12-23c=7(9-c):

12-23c=7(9-c)  Eliminate the parantheses using the distributive property

12-23c=63-7c  Add 23c to both sides; subtract 63 from both sides

-51=16c          Divide both sides by 16

`c=-51/16=-3.1875`

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The solution is `c=-51/16=-3.1875`

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Payal Khullar | College Teacher | (Level 2) Associate Educator

Posted August 8, 2013 at 9:44 PM (Answer #2)

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12 - 23c = 7 (9 - c)

Let's start by solving the bracket on RHS:

`=>`  12 - 23c = (7X9) - 7c

`=>`  12 - 23c = 63 - 7c

Regrouping parts of the equation:

`=>`  -23c + 7c = 63 - 12

Solving for c:

`=>`  -16c = 51

`=>`  c = -51/16

Hence, the value of is -51/16.

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idontlikeschool0 | Student, Grade 11 | Honors

Posted January 6, 2013 at 2:52 AM (Answer #2)

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This is the equation you should solve.

12-23c=7(9-c) you should distribute 7 from the 9 and -c.

12-23c=63-7c

-12      -12

-23c=51-7c

+7c      +7c

-16c=51

/-16   /-16

c=-3.1875 So the answer is -3.1875.

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jess1999 | Student, Grade 9 | Valedictorian

Posted July 14, 2014 at 10:03 AM (Answer #3)

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12 - 23c = 7 (9-c) 

First distribute the 7 on the left side

By distributing, you should get

12 - 23c = 63 - 7c now add 7 on both sides

By adding, you should get

12 - 16c = 63  now subtract 12 on both sides

By subtracting, you should get

-16c = 51 now divide -16 on both sides

By dividing, you should get

C = -51/16 which is your answer

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