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What is the answer for the equation 4|x+1/3|=20 ? A.x=411/12or-411/12 B.x=411/12 C.x=42/3or-51/3D.no solution

User Rzysia
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2 Answers

1 vote

4|x + (1)/(3)| = 20


|x + (1)/(3)| = 5


x + (1)/(3) = 5 or
x + (1)/(3) = -5


x = 5 - (1)/(3) or
x = -5 - (1)/(3)


x = 4 (2)/(3) or
x = -5 (1)/(3)
User Cahit
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6 votes
Selection C is appropriate.

Divide by 4, unfold, subtract 1/3.
.. |x +1/3| = 5
.. -5 = x +1/3 . . . . one choice for the sign of the content of |x +1/3|
.. -5 1/3 = x

.. x +1/3 = 5 . . . . the other choice
.. x = 4 2/3

_____
If this were an inequality |x +1/3| < 5, I would "unfold" it as
.. -5 < x +1/3 < 5 . . . . . . . copy the right side expression to the left with reversed sign.
The above is an approximation of that. You can't really write -5 = ( ) = 5, because it is a gross violation of the equal sign. But you can write the two versions:
.. -5 = ( )
.. ( ) = 5
What is the answer for the equation 4|x+1/3|=20 ? A.x=411/12or-411/12 B.x=411/12 C-example-1
User Mike Loux
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8.7k points