Question

Write an equation for a circle with a radius of 3 and a center located at point (2,-1)

Answer 1

(x - 2)^2 + (y + 1)^2 = 9

Explanation:

recall the equation for a circle:

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

here (h, k) = (2, -1)

and r = 3

so

(x - 2)^2 + (y -(-1))^2 = 3^2

(x - 2)^2 + (y + 1)^2 = 3^2

(x - 2)^2 + (y + 1)^2 = 9