Answer:
[tex](x^2+2)(x^2+10)[/tex]
Step-by-step explanation:
[tex]x^4+12x^2+20=(x^4+2x^2)+(10x^2+20)[/tex] separating middle term
[tex]x^2(x^2+2)+10(x^2+2)[/tex] factoring out common denom.
[tex](x^2+2)(x^2+10)[/tex] combining
