#J, 9 bytes

+&.*:/-/> 

This is a function that takes one set of coordinates from the other (-/>), and then performs a sum + under &. square *:.

The input should be in the format x y z;a b c where x y z is your first set of co-ordinates and a b c is the other.

J, 9 bytes

+&.*:/-/> 

This is a function that takes one set of coordinates from the other (-/>), and then performs a sum + under &. square *:.

The input should be in the format x y z;a b c where x y z is your first set of co-ordinates and a b c is the other.