[eli5] Trying to teach to an autistic child why 4 – (-2) is 4 +2.

Question

Title. I know it goes like that, but as an non mathematician can’t explain it to him.

In: 0

Answer 1

I would explain it in terms of debt. If I have 4 brownies, and then Timmy loans me 2 brownies, how many brownies do I get to eat if I “subtract” Timmy permanently if you know what I mean.