Help with destroy and delete HABTM

I have this code in rp_parts controlled in def destroy:

    @repair_ticket.rp_parts.delete(@rp_part)

repair_tickets and rp_parts are HABTM.

If I do:

repair_ticket1.rp_parts

=> [#<RpPart id: 1, ...">, #<RpPart id: 1,...">, #<RpPart ...">]

I only want to delete one of those RpPart id:1, and not both of them. Is
it possible?

John Smith wrote:

I have this code in rp_parts controlled in def destroy:

    @repair_ticket.rp_parts.delete(@rp_part)

repair_tickets and rp_parts are HABTM.

If I do:

repair_ticket1.rp_parts

=> [#<RpPart id: 1, ...">, #<RpPart id: 1,...">, #<RpPart ...">]

I only want to delete one of those RpPart id:1, and not both of them. Is
it possible?

Consulting the API, I found that:

.delete:
Deletes the record with the given id without instantiating an object
first. If an array of ids is provided, all of them are deleted.

What if I only want to delete the first one?