## anonymous 5 years ago x^2 + 3x - 28 = 0

1. anonymous

2. anonymous

Factor it first.

3. anonymous

my math teacher said not to factor first :/

4. anonymous

Have you learned the quadratic formula?

5. anonymous

yeaa

6. anonymous

$x = \frac{-b \pm \sqrt{b^2-4ac}}{2a}$ In this case a =1 , b = 3 and c = -28

7. anonymous

like i no how to get this far. x^2 + 3x = 28 and i no that is the first step, then, you are supposed to cut the 3x in half and square it. but im confused because it is a prime and odd number!

8. anonymous

What are you trying to achieve with that equation? Are you trying to find the zeros?

9. anonymous

im trying to find the x and the directions say " solve by completing the square."

10. anonymous

ahhh there you go now we can do something with that.

11. anonymous

Visit this site. Hope it helps. http://www.purplemath.com/modules/sqrquad.htm

12. anonymous

k thanks!