Earlier in the class, we learned how to solve quadratic equations by factoring. This works fine, as long as we are able to successfully complete the factoring step. For quadratics that cannot be factored, we will need to turn to alternative methods.

There are two methods we will use, the square root property (which is relatively simple, but doesn’t work in all cases), and the quadratic formula (which works for *all* quadratic equations).

This video gives a basic example of the square root property:

The next video includes several examples, both simple and more complicated, using the square root property:

The** quadratic formula** is a single formula that allows us to solve *any* quadratic equation, regardless of whether we can factor it or apply the square root property. It is important when using the quadratic formula to first put the equation in *standard form* (make it equal to zero), so that you can correctly identify the numbers *a*, *b, *and *c *before plugging in.

Here are two examples of using the quadratic formula to solve a quadratic equation:

Pro Reitz,

although i was confused with the first equation, later on i got a hang of it. the formula is a long one so I’m a bit scared of forgetting it, or misplacing signs.

Professor Reitz,

As you explained to me why I must get rid of the ^2 for the square root property, I was still a bit confused. The example used was (x-1)^2=12

Justen Garner

Professor Halleck

I think that the quadratic equation is the best way to solve any quadratic equation. It might be longer than the other two methods but it gives you the right answer 95% of the time.

Eda Ocello

Professor Halleck

It took me a while to remember the formula but once i keept doing problems and re-writing it over and over again i started to memorize it and get the hang of it. As long as I remember how to do the formula I have no other problems with quadratic equations. Its pretty easy actaully.

Candice Wright

Prof. Halleck

Todays class was pretty easy, I understood everything.

Professor Reitz

I’m Glad we spent a lot of time today in class going over the test rewiew sheet because there were many things i wasn’t sure of but today i grasped the concept, the videos were also very helpful. once you memorize the formula you cannot go wrong it will work with every quadratic equation which i think is great. i just hate that we have to go back to geometry

Today’s lesson was easy.

Pro. Halleck

so I wasn’t in class to learn this but I kind of got it, kinda