Finding center, radius and intercepts of x² + y² - x + 2y + 1 = 0

  • Thread starter Thread starter elitespart
  • Start date Start date
  • Tags Tags
    Circle Graphing
Join the discussion
Registration is free. Start your own thread to ask a follow-up.
3 replies · 2K views
elitespart
Messages
95
Reaction score
0
Consider x^2 + y^2 – x + 2y + 1 = 0.
(a) Find the coordinates of the center and the length of the radius.
(b) Determine the coordinates of the intercepts.
(c) Graph the circle.



I'm really lost on this one. I tried plugging in numbers but I seriously doubt that's how I'm supposed to do it. Can someone point me in the right direction? Thanks
 
Physics news on Phys.org
Standard Form versus General Form.
Completing the Square.
 
oh so just (x-1/2)^2 + (y+1)^2 = 1/4? center would be at (1/2, -1) and radius is sqrt(1/4)=(1/2)?
 
elitespart said:
oh so just (x-1/2)^2 + (y+1)^2 = 1/4? center would be at (1/2, -1) and radius is sqrt(1/4)=(1/2)?

Yup! :biggrin: