What is the standard form of the equation of a circle whose diameter is 12 units and whose center is (-2,9) ?

(x + 2) ² + (y - 9) ² = 36

Step-by-step explanation:

Equation of a circle is:

(x - h) ² + (y - k) ² = r²

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

Here, the center is (-2, 9) and the radius is 12/2 = 6.

(x + 2) ² + (y - 9) ² = 36