<s>[INST] Solve the inequality $2\left|x+\frac{1}{4}\right| < 9$
I keep trying to figure this out and I can't.
I tried to split up the absolute value first.
$2 (x+\frac{1}{4}) < 9$
$2+x+\frac{1}{4} < 9$ 
subtract $2$ from both sides? $x+\frac{1}{4} < 7$
and
$2 -(x+\frac{1}{4}) < 9$ 
$2-x-\frac{1}{4} < 9$
subtract $2$ from both sides? $-x-\frac{1}{4} < 7$
well that's not right. I suck at this. :c
Thanks for any helpers.
 [/INST] Write $2|\frac{x+1}{4}|<9$ as $\frac{-9}{2}<\frac{x+1}{4}<\frac{9}{2}.$ This gives $-18<x+1<18$ which is $-19<x<17$
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