There are a couple of ways to see if the Address was added using the Add relationship form, meaning the address is linked and can be updated from the organization's record if changes are made.

The address on the primary contact's record will have the Contact Address indicator as seen below.
Contact Address indicator on the Address record from the Individual's contact tab

Another way to see if the address is linked is the Addresses\Relationship fields in a constituent ad-hoc query. If the address was added using the Add relationship form, the Addresses\Relationship\Constituent name, Addresses\Relationship\Addresses\Address, Addresses\Relationship\Relationship type, and similar fields will be populated. If the addresses are not linked, those fields will not have values present.