side note; there are some subtleties here for the rationals and serious difficulties with this method for irrationals. I agree this is a good start for someone

side note; there are some subtleties here for the rationals and serious difficulties with this method for irrationals. I agree this is a good start for someone thinking about how to prove some simple math ’rules’ though, so please don’t take this as discouragement; rather encouragement to keep opening up minds when discussing math!