



 
Hi Kelly, If the line segment from (4, 4, 4) to (8, 8, 8) is a diameter of the sphere then the midpoint of this diameter is the center of the sphere. Can you find the midpoint of this diameter? If the line segment from (4, 4, 4) to (8, 8, 8) is a diameter of the sphere then the half the length of this diameter is the radius of the sphere. Can you find half the length of this diameter? Now you have the center and the radius of the sphere can you write its equation? Write back if you need more help,  


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