SOLUTION: Find the center and radius for the circle defined by the equation: x2 + y2 + 5x − y + 2 = 0

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Question 747502: Find the center and radius for the circle defined by the equation: x2 + y2 + 5x − y + 2 = 0
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
Put in "standard form" of a circle:
(x-h)^2 + (y-k)^2 = r^2
.
x^2 + y^2 + 5x − y + 2 = 0
x^2 + y^2 + 5x − y = -2
x^2 + 5x + y^2 − y = -2
(x^2 + 5x) + (y^2 − y) = -2
(x^2 + 5x+ 25/4) + (y^2 − y + 1/4) = -2 +25/4+1/4
(x^2 + 5/2)^2 + (y^2 − 1/2)^2 = -8/4 +25/4+1/4
(x^2 + 5/2)^2 + (y^2 − 1/2)^2 = (-8+25+1)/4
(x^2 + 5/2)^2 + (y^2 − 1/2)^2 = 18/4
(x^2 + 5/2)^2 + (y^2 − 1/2)^2 = (3sqrt(2)/2)^2
.
center: (-5/2, 1/2)
radius: 3sqrt(2)/2