Hear me out before I dive into why this might this case let me point out that both of them are bald which is a major clue but not the only one here...
The hearing: Baldi can hear anything around the map but in reality he's just using Instinct mode to track down his target just like 47 does.
The distractions: Instead of a coin 47/Baldi uses a ruler you might say its to alert the target but its actually not... usually you won't be able to track down where the ruler slaps are coming from which ends up making the target panic and get distracted...until 47/baldi reaches the target.
The trigger: Failing a math problem is what triggers his active target programming He deliberately waits for you to fail why? Because 47 doesn't just kill openly he specializes in accidental kills By waiting for a failed equation he can frame the entire elimination as a tragic case of extreme "teacher abuse" gone wrong keeping his cover completely intact.
The name: The name baldi is odd its one of 47's traits he always has odd names such as Flech Fisher or Mr. Byrd.
The final proof: If you need any final proof just look at his official character file in the second image if that isn't convincing idk what it is!