In the xy-plane, a circle with radius 5 has center . Which of the following is an equation of the circle?
Choice B is correct. An equation of a circle is , where the center of the circle is
and the radius is r. It’s given that the center of this circle is
and the radius is 5. Substituting these values into the equation gives
, or
.
Choice A is incorrect. This is an equation of a circle that has center . Choice C is incorrect. This is an equation of a circle that has center
and radius
. Choice D is incorrect. This is an equation of a circle that has radius
.