where are the "x"s to remove e-mail addresses at Apple ID support page?

You cannot remove an Apple ID. You can only stop using it. Apple alone can delete an Apple ID.

For Problems With Your Apple ID

1. Forgot iCloud Password
2. Forgot Apple ID
3. Apple ID - Apple Support
4. Manage your Apple ID primary, rescue, alternate, and notification email addresses - Apple Support
5. About your Apple ID email addresses - Apple Support
6. Get help with Apple ID

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Which Apple Support page? More information would help. What are you trying to accomplish?