Question 84266
ok get all terms to one side, you do that by adding 18m to both sides, you get
{{{m^2+18m+81=0}}}
this factors into {{{(m+9)(m+9)=0}}}
so {{{m+9=0}}}
{{{m=-9}}} 
since the second part of parenthesis is the same you got only one solution, which is m=-9