How do you solve $abs(2/3x-9)=18$ ?

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Answer 1 · 2017-05-19T09:14:11

$x=-27/2$
$x=+81/2$

For this to work we have to end up with $|+-18|=+18$

This means that $" "2/3x-9=+-18$

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Case 1: $" "2/3x-9=+18$

Add 9 to both sides

$2/3x=27$

Multiply both sides by $3/2$

$x=3/2xx27 = 40 1/2 ->81/2$
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Case 2: $" "2/3x-9=-18$

$2/3x=-9$

$x=3/2xx(-9)=-27/2$

How do you solve abs(2/3x-9)=18abs(2/3x-9)=18?