Quantcast

Got Homework?

Connect with other students for help. It's a free community.

  • across
    MIT Grad Student
    Online now
  • laura*
    Helped 1,000 students
    Online now
  • Hero
    College Math Guru
    Online now

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

whadduptori Group Title

Use the quadratic formula to solve the equation? 4x2 – 6x – 10 = 0 is anybody able to show me work?

  • one year ago
  • one year ago

  • This Question is Closed
  1. Rezz5 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    the quadratic formula is -b (±)Sqrt[b-4ac]/2a\[-b \pm \frac{ \sqrt{b-4ac}}{ 2a}\]

    • one year ago
  2. Rezz5 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    where ax^2 +bx +c just substitute and you will get your answer.

    • one year ago
  3. jim_thompson5910 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    \[\Large x = \frac{-b\pm\sqrt{b^2-4ac}}{2a}\] \[\Large x = \frac{-(-6)\pm\sqrt{(-6)^2-4(4)(-10)}}{2(4)}\] \[\Large x = \frac{6\pm\sqrt{36-(-160)}}{8}\] I'll let you finish.

    • one year ago
  4. whadduptori Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    I have all that work! I just get confused with the last part? like would i subtract 36-(-160)

    • one year ago
  5. Rezz5 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    36--160? well double negative is positive, so? 36+160

    • one year ago
  6. jim_thompson5910 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    36-(-160) is the same as 36+160

    • one year ago
  7. whadduptori Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    so it would become 196?

    • one year ago
  8. jim_thompson5910 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    it would

    • one year ago
  9. whadduptori Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    |dw:1352933217966:dw|

    • one year ago
  10. whadduptori Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    so would that be the answer?

    • one year ago
  11. jim_thompson5910 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    you can keep going and there's a +- between the 6 and square root

    • one year ago
  12. jim_thompson5910 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    you should have \[\Large x = \frac{6\pm\sqrt{196}}{8}\] but you can keep going

    • one year ago
  13. Rezz5 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    (6*14)/8 =(3*14)/4 =(3*7)/2 =21/2

    • one year ago
  14. whadduptori Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    yes i have that!

    • one year ago
  15. Rezz5 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    okay, what is wrong?

    • one year ago
  16. whadduptori Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    wait where did you get the 6*14/8

    • one year ago
  17. jim_thompson5910 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    the square root of 196 is 14, so... \[\Large x = \frac{6\pm\sqrt{196}}{8}\] becomes \[\Large x = \frac{6\pm14}{8}\]

    • one year ago
  18. Rezz5 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    above is very clear and correct, so first you do the plus sign which is (6+14)/8 this is ONE OF YOUR x's the you do (6-14)/8 this is your other x value so your x values are: 5/2 and -1

    • one year ago
  19. whadduptori Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    THank you so much! I didnt know how to find that! but you just made it clear for me! thank you both for your help! (:

    • one year ago
  20. Rezz5 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    your most welcome,

    • one year ago
    • Attachments:

See more questions >>>

Your question is ready. Sign up for free to start getting answers.

spraguer (Moderator)
5 → View Detailed Profile

is replying to Can someone tell me what button the professor is hitting...

23

  • Teamwork 19 Teammate
  • Problem Solving 19 Hero
  • You have blocked this person.
  • ✔ You're a fan Checking fan status...

Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.

This is the testimonial you wrote.
You haven't written a testimonial for Owlfred.