SOLUTION: Identify the center and radius of the circle with the given equations. x^2 + y^2 + 8y -9 = 0

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Question 1186656: Identify the center and radius of the circle with the given equations.
x^2 + y^2 + 8y -9 = 0
Answer by ikleyn(52803) About Me  (Show Source):
You can put this solution on YOUR website!
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Transform given equation to the standard equation of a circle.


    x^2 + y^2 + 8y -9 = 0


    x^2 + y^2 + 8y = 9


    x^2 + (y^2 + 8y + 16) = 9 + 16


    x^2 + (y^2 + 4)^2 = 25


The circle with the center at (0,-4) and the radius of 5.    ANSWER

Solved.