If I can't factor a quadratic equation what will I do??

I don't know the latex for this.. thanks. I tried extracting the roots but it turned out as square root of a negative number?? Am I in the right track?

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- Mar 23rd 2009, 06:15 AMprincess_21[SOLVED] help
If I can't factor a quadratic equation what will I do??

I don't know the latex for this.. thanks. I tried extracting the roots but it turned out as square root of a negative number?? Am I in the right track? - Mar 23rd 2009, 06:30 AMskeeter
- Mar 23rd 2009, 06:32 AMprincess_21
- Mar 23rd 2009, 06:44 AMSirNostalgic
This means theres no intersection with the x-axis. if you simply need to sketch the graph find the turning point of the quadratic should give you the X-coordinate of the turning point. Put that X-coordinate value into the non-differentiated equation and you'll get your Y-coordinate of the turning point

- Mar 23rd 2009, 06:49 AMprincess_21
- Mar 23rd 2009, 06:50 AMSirNostalgic

x = -1 is the x-coordinate of the Turning point, plug into the original equation for the Y-value of this Turning point

= 6

Coordinates of Turning point (-1,6) I'm guessing this is a minimum :p

i swear to god my computer pasted what i wrote twice. What in gods name happened there lol - Mar 23rd 2009, 06:59 AMstapel
**Graph the quadratic**. Look at the picture. Look at the inequality.

You are asked to find the x-values for which the quadratic is at or above the x-axis. What does the picture show you?

(Wink) - Mar 23rd 2009, 07:06 AMprincess_21
- Mar 23rd 2009, 07:31 AMstapel
If the various worked examples in the lesson (provided in the link) were not sufficiently helpful, then try studying a few more

**online lessons**. (I'm assuming you understand the x,y-plane and how to graph linear equations.)

Once you've learned how to do the graph, draw the picture. (Wink) - Mar 23rd 2009, 07:46 AMADARSH
A simple answer to your question is

-Roots are not real as square root of negative is not real

-Meaning graph never touches x axis , or in other words the quadratic function never has zero value

-This means that the quadratic is either always positive or always negative

(since to change from +ve to -ve you need to cross 0 )

**Result:**

Value of equation for all x is either always positive or always negative

----------------------------

**Application**:

Put x = any number , lets take it as 2

15>0, as derived earlier for all values of x this is equality holds that

thus answer is every real x

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No real need to draw a graph or learning it for answering this - Mar 23rd 2009, 08:07 AMprincess_21
- Mar 23rd 2009, 08:10 AMADARSH
- Mar 23rd 2009, 08:13 AMprincess_21
- Mar 23rd 2009, 08:14 AMprincess_21
Thank you everyone for your help.. I think I need to read more about this..