If anything F-15 borrowed more from Mig-25 (earlier than F-15 design), and F-16 looks a lot like a 1962 Mig-21 variant (Mig-21M aka E-8 earlier than F-16 design).
Just browse for a pictures of both Mig-25 and E-8 and keep in mind both were earlier designs to F-15 and F-16.
That sir just confirms what I posted and you questioned.
Have a nice day now that your questions posed have been answered.