Question 672491
You don't have to worry about negative values
inside the absolute value because the expression
can never be more negative than {{{ -9 }}}
So I can say
{{{ x^2 - 9 = 16  }}}
{{{ x^2 = 25 }}}
{{{ x = 5 }}}
{{{ x = -5 }}}
either value for {{{x}}} works