Absolute Value Equations: Solving |2x-8| + |12-3x| = 0

AI Thread Summary
To solve the absolute value equation |2x-8| + |12-3x| = 0, recognize that the sum of two absolute values can only equal zero if both expressions are individually zero. This leads to the equations 2x - 8 = 0 and 12 - 3x = 0, resulting in x = 4 for both cases. The solution is confirmed as x = 4, since it satisfies both absolute value conditions. The confusion arose from incorrectly manipulating the absolute values and not recognizing that both must equal zero simultaneously. Understanding this principle is crucial for solving similar absolute value equations effectively.
Nelo
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Homework Statement



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



Homework Equations



what do i do when it = 0

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 don't know what.

So , here's 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?
 
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Nelo said:

Homework Statement



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



Homework Equations



what do i do when it = 0

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 don't know what.

So , here's 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|
 
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