A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

anonymous

  • 5 years ago

how do you find the formula for the top half of a circle w/ center (-1,2) radius 3

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

    The general equation for a circle is x^2 + y^2 = r^2, where r is the radius. The center of this circle is the origin. To move it to some other point, we'll call it (h, k), replace x with (x - h) and y with (y - k) in the equation above. You have h, k, and the radius, so just plug in and you're done. Now, to restrict this to the top half, solve for y. The other side of the equation will have a square root with +/- in front of it. One sign is the upper half, the other sign is the lower half. That give you enough to go on?

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

    Thank you for responding! I don't want to move the circle, I am just trying to find the formula for the function. The answer is y=2+√9-(x+1)^2 Does that make sense to you?

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

    Actually, you do want to move the circle -- you want the center at (-1, 2) instead of at (0, 0). So -1 is h and 2 is k: (x- (-1))^2 + (y - 2)^2 = 3^2. Solving that for y and taking only the positive square root will give you the result above.

  4. 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.