What is the equation of a circle that has radius #r# centred on the origin?
1 Answer
Jul 6, 2017
# x^2 + y^2 = r^2 #
Explanation:
The standard equation of a circle with centre
# (x-a)^2 + (y-b)^2 = r^2 #
Thus the equation we seek with centre
# (x-0)^2 + (y-0)^2 = r^2 #
i.e.
# x^2 + y^2 = r^2 #