Question 1100916
The two "1" digits appear to be meant as absolute value symbols.


{{{abs(2x+1)=11}}}


The expression {{{2x+1}}} might be negative or non-negative.
Either  {{{2x+1=11}}} or {{{-(2x+1)=11}}}.


Solving for BOTH:


{{{2x+1=11}}}
{{{2x=10}}}
{{{x=5}}}
OR
{{{-2x-1=11}}}
{{{-2x=12}}}
{{{x=-6}}}


RESULT:
{{{system(Either,x=5,OR,x=-6)}}}