



 
Hi Mikee, The circle \[x^2 + y^2 = 4\] has center $(0,0)$ and radius $\sqrt{4} = 2.$ I drew a diagram. What is the radius of a circle with center $(0,5$ and tangent to the circle in the diagram? What is its equation. Why does the problem say "find the equation of A circle..." rather than "find the equation of THE circle..."? Is there more than one answer? Penny  


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