Question 10773
{{{4x^4 - 18x^2 = 0}}}


Factor the common factor first, which is {{{2x^2}}}

{{{2x^2( 2x^2 - 9) = 0 }}}


Two separate solutions:


First: 
{{{2x^2 = 0}}}
{{{x^2 = 0}}} so {{{x=0}}}


Second:  
{{{2x^2 - 9 = 0}}}
{{{2x^2 = 9}}}
{{{x^2 = 9/2}}}


Take square root of both sides:

{{{x = sqrt(9/2)}}} or {{{x = -sqrt(9/2) }}}
{{{x = 3/(sqrt(2))}}} or {{{x= -3/(sqrt(2)) }}}


Another possible way to write the last answers is this:
{{{x = (3*sqrt(2))/2}}} or {{{x= (-3*sqrt(2))/2}}}


R^2 at SCC