How to Use the Quadratic Formula to Never Factor Polynomials Again

We learn to factor polynomials so we can solve for x. Stuff like

3x² + 2x – 1

can be easily factored into

(3x – 1)(x + 1)

But some things aren’t so easy. And some things are just down right a pain in the bottom. Like this one:

18x² + 189x + 490

“Just shoot me,” you might be thinking. But cool your jets, cowboy. Here’s the first tool you need to never factor polynomials again:

I know – who wants to memorize that formula? But wait. If you use that one formula that you can memorize, you never have to factor polynomials again. Watch:

So the factoring isn’t bad on that one, right? How about this one:

And how about if you come across one of these. Wouldn’t it be nice to get rid of all guesswork:

This has some disadvantages, of course. You see that there’s a lot more arithmetic. And there’s some things to look out for. But if you hate trial and error (like I do), then you might be willing to take the bad with that good.

Whatcha think?