Unfortunately, this can't be factored. The only other way I know to find the solutions to a quadratic equation is with the use of the quadratic formula. When you do that, you get these solutions:
t = 2 + √7 = about<em> 4.65</em> and t = 2 - √7 = about <em>-0.65</em> .
If this equation comes from a problem that involves real people throwing real things into the air and making vertical motion, then you want only the positive solution.