Question 637696
{{{36x^2-81=0}}}...both sides divide by {{{9}}}

{{{36x^2/9-81/9=0/9}}}

{{{4x^2-9=0}}}

{{{(2x)^2-3^2=0}}}

{{{(2x-3)(2x+3)=0}}}


solutions:

{{{(2x-3)=0}}}......->..{{{2x=3}}}....->..{{{x=3/2}}}
and
{{{(2x+3)=0}}}......->..{{{2x=-3}}}....->..{{{x=-3/2}}}