## anonymous one year ago Find the x-intercepts (if any) for the graph of the quadratic function. 6x2 + 12x + 5 = 0 Give your answers in exact form. Show your work.

1. anonymous

@Hero @dan815

2. anonymous

@Jhannybean @satellite73 @Loser66 @freckles @EclipsedStar @King.Void. @sleepyjess can someone help me please?

3. sleepyjess

Do you have an idea on how to start?

4. anonymous

no not at all

5. sleepyjess

Do you know what the quadratic formula is?

6. anonymous

what you mean?

7. sleepyjess

$$x=\dfrac{-b\pm\sqrt{b^2-4ac}}{2a}$$

8. sleepyjess

That is the quadratic formula

9. sleepyjess

It may look intimidating, but it's not too bad once you know how to work it :)

10. anonymous

Okay how do I work it lol..

11. sleepyjess

A quadratic equation is ALWAYS "Ax^2 + Bx + C = y" To use the quadratic formula, you will want to substitute 0 for y, which has already been done. Can you figure out what A, B, and C are in the quadratic equation you have?

12. anonymous

A= 6x^2 B= 12x C= 5

13. sleepyjess

Close, but we just want 6, 12 and 5

14. anonymous

Ohh lol

15. sleepyjess

So now we just substitute in 6 for a, 12 for b, and 5 for c then work out the equation

16. anonymous

I got down to $x= \frac{ -12\pm \sqrt{24} }{ 12 }$ now what do I do?

17. anonymous

@sleepyjess

18. carolinar7

Now simplify what you have there

19. anonymous

How?

20. carolinar7

$x=\frac{ -12-+4\sqrt{6} }{ 12 }$

21. carolinar7

Can you simplify any further?

22. anonymous

Why 4 sqrt7 instead of sqrt24=4.89....?

23. anonymous

I meant sqrt6 sorry

24. carolinar7

Sorry let me correct myself it is 2sqrt6

25. carolinar7

Is this Alg. 1

26. anonymous

How!? And no its pre-calculus

27. carolinar7

what grade ar you in

28. anonymous

29. carolinar7

me too im in pre-calc in 9th grade

30. sleepyjess

oh goodness, I forgot about the square root simplifying >_<

31. anonymous

How do I do that?

32. sleepyjess

@carolinar7 simplified it for you

33. carolinar7

what do you mean you simplified it for me

34. sleepyjess

you simplified the square root already

35. anonymous

2 sqrt6?

36. carolinar7

It is not completely simplified though, you can simplify further too

37. carolinar7

$x=\frac{ -6+-\sqrt{6} }{ 6 }$

38. anonymous

so where do I go from $x= \frac{ -12 \pm 2\sqrt{6} }{ 12 }$

39. anonymous

Ohhh how did you get that?

40. carolinar7

You simplify it and divide by 2 because that is what they share in common

41. anonymous

Ohhh okay soo now I do -6/6?

42. carolinar7

|dw:1443753373282:dw|

43. carolinar7

no you cant simplify any further

44. anonymous

so thats the exact form?

45. carolinar7

Wait let me do it on a paper

46. carolinar7

Yes that is the most you can simplify it

47. anonymous

Okay thank you!

48. carolinar7

yup