Question 584189
{{{x^4 - 10x^2 + 9}}}seperate and group them
{{{(x^4 - x^2)+(-9x^2 + 9)}}} factor out what is needed x^2 and -9
{{{x^2(x^2 - 1)+(-9)(x^2 - 1)}}} factor out x^2-1
{{{(x^2-1)(x^2-9)}}} these are perfect squares factor them to below
{{{(x-1)(x+1)(x-3)(x+3)}}} set = to 0 to solve for x
x=1,-1,3,-3