The center of a circle is located at (6, −1) . The radius of the circle is 4.
What is the equation of the circle in general form?
A.) x2+y2−12x+2y+21=0
B.) x2+y2+12x−2y+33=0
C.) x2+y2+12x−2y+21=0
D.) x2+y2−12x+2y+33=0
First write in center-radius form
( x - 6)^2 + ( y + 1)^2 = 16 expand
x^2 - 12x + 36 + y^2 + 2y + 1 = 16 simplify
x^2 + y^2 - 12x + 2y + 21 = 0 ...... "A" is correct
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