Question

Whats the equation for center (-2,8) and radius 9

Answer 1

(x + 2)² + (y - 8)² = 81

Explanation:

The equation of a circle in standard form is

(x - h)² + (y - k)² = r²

where (h, k) are the coordinates of the centre and r is the radius

Here (h, k) = (- 2, 8) and r = 9, thus

(x - (- 2))² + (y - 8)² = 9², that is

(x + 2)² + (y - 8)² = 81