SOLUTION: Find the center and the radius of the circle x+1 squared + y+4 squared =81.

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Question 239020: Find the center and the radius of the circle x+1 squared + y+4 squared =81.
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
(x+1)^2 + (y+4)^2 = 81



the center of this circle should be at (x,y) = (-1,-4).

Graph of your equation seems to confirm that.

In order to graph, you need to solve for y.

the solved equation is:

y = -4 +/- sqrt(81-(x+1)^2)

It looks like your original equation is in the form of (x-h)^2 + (y-k)^2 = r^2 where:

h = x coordinate of the center of the circle.
k = y coordinate of the center of the circle.
r = the radius of the circle.