SOLUTION: Complete the square and write the equation of the circle in standard form. Then determine the center and the radius of the circle to graph the equation.
x^2+y^2+8x+6y+9=0
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-> SOLUTION: Complete the square and write the equation of the circle in standard form. Then determine the center and the radius of the circle to graph the equation.
x^2+y^2+8x+6y+9=0
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Question 763199: Complete the square and write the equation of the circle in standard form. Then determine the center and the radius of the circle to graph the equation.
x^2+y^2+8x+6y+9=0 Answer by Cromlix(4381) (Show Source):
You can put this solution on YOUR website! x^2 + y^2 + 8x + 6y + 9 = 0
Separate the x's and y's
(x^2 + 8x) + (y^2 + 6y) + 9 = 0
Completing the square on x's
(x^2 + 8x + 4^2) - 4^2
(x + 4)^2 - 16
Completing the square on y's
(y^2 + 6y + 3^2) - 3^2
(y + 3)^2 -9
Putting back into equation:-
(x^2 + 8x) + (y^2 + 6y) + 9 = 0
((x + 4)^2 - 16)+((y + 3)^2 - 9) + 9 = 0
(x + 4)^2 + (y + 3)^2 -16 -9 + 9 = 0
(x + 4)^2 + (y + 3)^2 - 16 = 0
(x + 4)^2 + (y + 3)^2 = 16
Centre (-4, -3) Radius = 4
