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hollz0143
Sep 21, 2005, 05:25 PM
it says write the standard form of the equation and the general form of the equation of each circle of radius r and center (h,K). By hand graph each circle

r=2; (h,k) = (-2,1)

reinsuranc
Sep 24, 2005, 06:36 PM
The equation of a circle with center x=h and y=k and radius r, is:

(x - h)^2 + (y - k)^2 = r^2. Here I am using the symbol ^ to indicate exponentiation.

In your example, h=-2, k=1, r=2.

(x - -2)^2 + (y - 1)^2 = 2^2, or

(x + 4)^2 + (y - 1)^2 = 4.

You need to draw a graph of a circle with center (-2,1) and radius 2.