Removing this type of supply line from bathroom faucet
 

Dear experts,

I am trying to replace an old faucet(16 years old),
I removed one nut around the supply line, but supply
line seems embedded inside the old faucet, I tried to pull
it down hard , but it didn't work.

Any suggestions on how to remove it ?
(see the attached the picture)

Thank you!

Grip the rubber washer with pliers, twist and pull. You may want to consider replacing the supply line too in which case you can just cut them off under the sink to allow you to remove the faucet.

kok328 , I like your idea to replace supply line. I will run home depot to
get parts ready and try it. Thanks!

Often, you can unfreeze parts like this with a brief shot of flame from your plumbing torch. Just heat it from the side, then grab the supply line with strong pliers and muscle it out. Throw away that supply line ... it sucks and you need a braided line for your new faucet anyway.

HAVE FUN! :D

Disconnect the other end and take them out with the old tap?