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Nelo
Sep13-11, 08:39 PM
1. The problem statement, all variables and given/known data

|2x-8| + |12 - 3x | = 0



2. Relevant equations

what do i do when it = 0

3. The attempt at a solution

I tried solving it like all the others, but i know there is a unique thing to do when it = 0, i jus dont know what.

So , heres what i did.

2|x-4| + -3|x-4| = 0
-|x-4| = 0

x > 4

(-)x-4 = 0
-x = 4
x = -4

x < 4

(-)-x+4 = 0
x+4 = 0
x = - 4.

The answer is 4, I just probably set the normal one up wrong, what am i doing wrong?

Mark44
Sep13-11, 09:11 PM
1. The problem statement, all variables and given/known data

|2x-8| + |12 - 3x | = 0



2. Relevant equations

what do i do when it = 0

3. The attempt at a solution

I tried solving it like all the others, but i know there is a unique thing to do when it = 0, i jus dont know what.

So , heres what i did.

2|x-4| + -3|x-4| = 0
-|x-4| = 0

x > 4

(-)x-4 = 0
-x = 4
x = -4

x < 4

(-)-x+4 = 0
x+4 = 0
x = - 4.

The answer is 4, I just probably set the normal one up wrong, what am i doing wrong?

|12 - 3x | = |3x - 12| = 3|x - 4|