x^2 + 2xh + h^2 + y^2 + 2ky + k^2 = r^2

or

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

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

This equation is of this form:

(x + h)^2 / a^2 - (y + k)^2 / b^2 = 1

Which is a hyperbola

x^2 - 8x - y^2 = 0
x^2 - 2 * 4 * x + 4^2 - y^2 = 4^2
(x - 4)^2 - (y - 0)^2 = 16
(1/16) * (x - 4)^2 - (1/16) * y^2 = 1

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