A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

anonymous

  • one year ago

Using the following equation, find the center and radius of the circle. You must show all work and calculations to receive credit. x2 + 2x + y2 + 4y = 20 Help me please I will give a medal and fan!!

  • This Question is Closed
  1. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    So far i have this x2 + 2x + y2 + 4y = 20 (x2 + 2x) + (y2 + 4y) = 20

  2. misty1212
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    H!!

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

    The radius is r = sqrt(25) = 5

  4. misty1212
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    complete mr square twice, once for each term

  5. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    I need help figuring it out though, i have no idea whatsoever ho to do this problem.

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

    @dan815 @Michele_Laino

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

    Can someone walk me through this please?

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

    for each to complete the square, take the coefficient on the linear x, y term and add to that quantity half of its square

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

    I honestly have no idea how to do that..

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

    So do i have to figure out that equation? I honestly dont think ill be able to learn this, ive been trying for about an hour

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

    (x^2 + 2x + 1^2 ) + (y^2 + 4y + 2^2) = 20 + 1^2 + 2^2 you take half the middle term and add the square of it , now you can do this (x+1)^2 + (y+2)^2 = 25

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

    http://www.mathsisfun.com/algebra/completing-square.html

  13. DanJS
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    the center of a circle in that form is (x - h)^2 + (y - k)^2 = r^2 here C(h,k) = C(-1 , -2) and r is the square root of 25

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

    so the radius is 25 and the center of the circle is 5?

  15. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    since 5 is the square root of 25

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

    the center is the point (h,k) or ( -1 , -2),, how far each point on the circle is away from that center; the radius, is the square root of 25, or 5

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

    r^2 = 25 r = 5

  18. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    i am so confused.....

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

    after you complete the squares, you have an equation in the form of ... (x-h)^2 + (y-k)^2 = r^2 r= radius, and (h,k) = the center point

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

    • Attachments:

Ask your own question

Sign Up
Find more explanations on OpenStudy
Privacy Policy

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.