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# 12+5k=15-4k

12+5k=15-4k

Posted by johnjacob87 on October 21, 2013 at 5:10 PM via web and tagged with how do i show my work ?, math

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`12+5k =15-4k`

`12+5k+4k =15`

`5k+4k =15-12`

`9k =3`

`k=3/9`

`k=1/3`  or equivalent ` k=0.(3)`

First, one needs to have on the left side of the equality the unknown terms and on the right side the known values. Thus we add `+4k` both to the left and to the right of the equality.

Then to have on the right side only known numbers, we add both to the left and to the right of the equality the number `-12` .

Finlay we divide by `9` both sides and simplify both the numerator and the denominator with `3` .

Answer: From the above equality we obtain `k=1/3`

Posted by valentin68 on October 21, 2013 at 5:26 PM (Answer #1)

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`12 + 5k = 15 - 4k`

`12 + 9k = 15`

Subtract 12 from each side.

`9k = 3`

Divide both sides by 9.

`k = 3/9 = 1/3`

The solution is k = `1/3.`

`12 + 5(1/3) = 15 - 4(1/3)`

`12 + 5/3 = 15 - 4/3`

Since 12 = `36/3`  and 15 = `45/3` , we have

`36/3 + 5/3 = 45/3 - 4/3`

`41/3 = 41/3`

The solution works.

Posted by baxthum8 on October 21, 2013 at 10:28 PM (Answer #2)

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eNoter

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`12+5k=15-4k`

combine like terms

`5k + 4k = 15 - 12`

`9k = 3 ` divide both sides by 9

`(9k)/9 = 3/9`

`3/9 `  both share a factor of 3 so you can simplify by dividing by 3

`3/ 9 -: 3/3 = 1/3`