\(\text{circle is centered at }(0,-8) \text{ and passes through }(2,-5)\)
\(\text{well it's easy enough to write down }\\ (x-0)^2 + (y-(-8))^2 = r^2\\ x^2 + (y+8)^2 = r^2\)
\(\text{but how to find }r^2 ?\\ \text{well every point on the circle is }r \text{ from the center}\)
\(r = \sqrt{(0-2)^2 + (-8 - (-5))^2} = \sqrt{4+9}=\sqrt{13}\\ \text{so we have}\\ x^2 + (y+8)^2 = 13\)
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