Tag: quadratic formula

  • How to Use the Quadratic Formula to Never Factor Polynomials Again

    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?