Why does multiplying two negative numbers equal a positive number?

Question

Why does multiplying two negative numbers equal a positive number?

In: 1210

Answer 1

Maths has to be consistent and beautiful. Things you don’t know must follow from things you already know to be true.

We know that positive times negative is negative:
2 * -3 = -6

Similarly negative over positive is negative
-6 / 2 = -3

And so is positive over negative
6 / -2 = -3

But for the latter to be true, it’s necessary that:
-2 * -3 = 6