Polyamory can't be the way to “solve” a love triangle, because you can't “solve” a situation. Solving only applies to a problem, and if you can simply be polyamorous, then being in love with two people isn't a problem.
A problem could be that both your love interests are very jealous, because one is intensely possessive and the other is deeply insecure. Then, instead of you feeling obliged to choose one of them (after which your chosen one would still continue to be jealous, just so you know), they could work through their emotional problems. That's solving a love triangle within the framework of polyamory. But it's not solved by polyamory. It's solved by… maybe therapy, or soul searching, or a spiritual journey to the underworld to defeat the ghosts of the parents who screwed up their perception of love but encountering their grandparents and great-grandparents too and learning to forgive, accept, and grow from a systemic understanding of the world, or something else.