I feel like they could have explained "minus times minus is a plus" using the distributive law. -1 x -1 = -1 * (0 - 1) = (-1 * 0) - (-1 * 1) Presu

I feel like they could have explained "minus times minus is a plus" using the distributive law. -1 x -1 = -1 * (0 - 1) = (-1 * 0) - (-1 * 1) Presumably at this point you were happy with "anything times zero is zero" and "anything times unity is itself", so: = 0 - (-1) and now we can just use the additive laws of negative numbers, which hopefully were intuitive enough: = 1