Hi Vance. I'm Greg, an installation specialist, 10 years awarded Windows MVP, and Volunteer Moderator, here to help you.
Go into the Photos App > Settings and look for the Sources folders that are being included in Photos app. Delete any that are not wanted, usually only the User Account Pictures folder. If only the correct Pictures app is included then it must mean the pictures are somehow getting into your User Account Pictures folder.
Are these sync'd from your phone, because a phone can have a weird habit of saving all of the visual components that make up a web page. The only way I've ever been able to reverse this is to Reset the phone. You could also turn off the Sync (OneDrive, iCloud, etc) that may be importing these into your Pictures folder or Photos app.
When did this first start? See if you can System Restore to a point before the problem began following this guide: https://www.windowscentral.com/how-use-system-r...
If none of the above help, can we see a screenshot of some of these pictures so we can spot where they might come from if we've seen them before? Obviously you wouldn't want to include any personal pictures. If these are more personal then please describe where you've seen them before.
To take a screenshot follow this guide to capture a screenshot and attach it using Attach Image button in reply box: http://windows.microsoft.com/en-us/windows-10/open-snipping-tool-and-take-a-screenshot
I hope this helps. Feel free to ask back any questions and keep me posted. If you'll wait to rate whether my post resolved your problem, I will keep working with you until it's resolved.
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