What is the equation of a circle with center (2, - 8) and radius 9?

A) (x + 2) 2 + (y - 8) 2 = 9

B) (x - 2) 2 + (y + 8) 2 = 9

C) (x + 2) 2 + (y - 8) 2 = 81

D) (x - 2) 2 + (y + 8) 2 = 81

D) (x - 2) ^2 + (y + 8) ^2 = 81

Step-by-step explanation:

The equation of a circle can be given by

(x-h) ^2 + (y-k) ^2 = r^2

where (h, k) is the center and r is the radius

We know the center is (2,-8) and the radius is 9

(x-2) ^2 + (y--8) ^2 = 9^2

(x-2) ^2 + (y+8) ^2 = 9^2

(x-2) ^2 + (y+8) ^2 = 81

Equation is (x - 2) ² + (y + 8) ² = 81

Step-by-step explanation:

Step 1: Given center is (h, k) = (2, - 8) and radius is 9. Equation of a circle is given by (x - h) ² + (y - k) ² = r²

Equation is (x - 2) ² + (y - - 8) ² = 9²

⇒ (x - 2) ² + (y + 8) ² = 81