Write the equation of the circle with the given center and radius.
-Center (0, 0),radius 9

Question

Quizplus · Accepted Answer

The equation of a circle with center (h,k) and radius r is (x-h)^2 + (y-k)^2 = r^2. 
Substituting the given values of center and radius, we get:
(x-0)^2 + (y-0)^2 = 9^2
Simplifying the equation, we get:
x^2 + y^2 = 81
Therefore, the correct choice is B, which matches this equation. The equation of a circle with center (h, k) and radius r is (x - h)^2 + (y - k)^2 = r^2. Substituting (0, 0) for (h, k) and 9 for r, we get x^2 + y^2 = 81, which is the equation of the circle with center (0, 0) and radius 9. Choice B is the correct answer.

Write the Equation of the Circle with the Given Center