SOLUTION: Can you please help me with this problem? i have to identify the conic section in standard form then graph. x^2+y^2-4y-5=0

Algebra ->  Quadratic-relations-and-conic-sections -> SOLUTION: Can you please help me with this problem? i have to identify the conic section in standard form then graph. x^2+y^2-4y-5=0      Log On


   

Question 522518: Can you please help me with this problem? i have to identify the conic section in standard form then graph. x^2+y^2-4y-5=0
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Identify the conic section:
x%5E2%2By%5E2-4y-5+=+0 Add 5 to both sides.
x%5E2%2B%28y%5E2-4y%29+=+5 Complete the square in y by adding 4 to both sides.
x%5E2%2B%28y%5E2-4y%2B4%29+=+5%2B4 Factor the group in y and simplify.
x%5E2%2B%28y-2%29%5E2+=+9 Compare this with the standard form for a circle of radius r with center at (h, k).
%28x-h%29%5E2%2B%28y-k%29%5E2+=+r%5E2 and you can see that you have a circle of radius 3 with center at (0,2).
I forgot the graph: