You can put this solution on YOUR website! x^2+x+1 cannot be factored because it is not a square trinomial. Subtract 1 from both sides, and then decide what to add to x^2+x to make it a square factorable trinomial! Study the derivation of Completing the Square. The term to add is (1/2)^2=1/4.
Knowing THAT, let's start from the original equation again and use the term.