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Solve[(x-x1)^2+(y-y1)^2+(z-z1)^2+(x-x3)^2+(y-y3)^2+(z-z3)^2==(x3-x1)^2+(y3-y1)^2+(z3-z1)^2&&(x-x1)^2+(y-y1)^2+(z-z1)^2+(x-x2)^2+(y-y2)^2+(z-z2)^2==(x2-x1)^2+(y2-y1)^2+(z2-z1)^2&&(x-x2)^2+(y-y2)^2+(z-z2)^2+(x-x3)^2+(y-y3)^2+(z-z3)^2==(x3-x2)^2+(y3-y2)^2+(z3-z2)^2,{x,y,z}]
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