Quantcast

A community for students. Sign up today!

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

abbie1

  • 2 years ago

.

  • This Question is Closed
  1. satellite73
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 2

    hello ambassador

  2. satellite73
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 2

    start with \[2x^2-8x+7=0\] then use \[x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}\] with \(a=2,b=-8,c=7\)

  3. saifoo.khan
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    @satellite73

    1 Attachment
  4. satellite73
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 2

    second step is \[x=\frac{8\pm\sqrt{8^2-4\times 2\times 7}}{2\times 2}\] then a bunch of arithmetic

  5. satellite73
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 2

    oh ok we compute \[\frac{8\pm\sqrt{64-56}}{4}\] \[=\frac{8\pm\sqrt{8}}{4}\] \[=\frac{8\pm2\sqrt{2}}{4}\] \[=\frac{2(4+\sqrt{2})}{4}\] \[=\frac{4+\sqrt{2}}{2}\]

  6. satellite73
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 2

    rewrite \(\sqrt{8}\) as \(2\sqrt{2}\) then factor and cancel details are above

  7. satellite73
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 2

    it is because \(\sqrt{8}=\sqrt{4\times 2}=\sqrt{4}\sqrt{2}=2\sqrt{2}\) in simplest radical form

  8. satellite73
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 2

    then be careful with factoring before you cancel the common factor of 2 top and bottom

  9. candyme
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Ok, you're going to multiply the terms in the radical\[x=\frac{8 \pm \sqrt{64-56}}{4}\]\[x= \frac{8 \pm \sqrt{8}}{4}\]\[x=\frac{8 \pm \sqrt{2*4}}{4}\]The 4 comes out as a 2 since the square root of 4 is 2\[x= \frac{8 \pm 2\sqrt{2}}{4}\]Divide by 2\[x=\frac{4 \pm \sqrt{2}}{2}\]

  10. satellite73
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 2

    it could be written as \[2\pm\frac{\sqrt{2}}{2}\]

  11. candyme
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Satellite is right, I was about to say that :)

  12. Not the answer you are looking for?
    Search for more explanations.

    • Attachments:

Ask your own question

Ask a Question
Find more explanations on OpenStudy

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.