This calculates the equation of a circle from the following given items:

* A center (h,k) and a radius r

* A diameter A(a

(x - h)

(1,1)(2,4)

(1,4) and (5,6)

(h,k) = (2,- 4) and r = 5

(x - 2)^2 + (y + 5)^2 = 81

Evaluate the circle equation (x - 2)

This circle equation is in standard form: (x - h)

From the standard form of a circle, we have h = -1 * -2 = 2

From the standard form of a circle, we have k = -1 * +5 = -5

Therefore, our circle has a center (h, k) = (2, -5)

Therefore, we have r

r = ±√81

Since a radius is always positive, we have r =

Expanding the standard form, we get the general form of x

Expanding the standard form, we get the general form of x

x

Combining our constants, we have our general form of a circle equation below:

To see the diameter, circumference, and area of this circle, visit our calculator

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Tags: center, circle, diameter, equation, midpoint, radius