What's the proof for a negative number times another negative number gives a positive number?
I'm studying arithmetic of numbers. I want to understand why the product of, say, -3 for -4 is 12 and not -12.Are you studying the arithmetic of numbers? Or are you studying something more advanced like algebra.
If you are studying algebra, perhaps what you want to see is a proof of something like
(-x)(-y) = xy. ( Strictly speaking a number like "-x" isn't necessarily "a negative" For example if x = -3 then -x is a positive number. )
Mark44 gave a good answer. I can't see your textbook, so I don' know what you have already studied from it. I have to guess what you already accept as true about numbers. The stepsI'm studying arithmetic of numbers. I want to understand why the product of, say, -3 for -4 is 12 and not -12.