Why a negative number times a positive number will give a negative number?

Becuase in the rule of laws of signs, when you multiply or divide a number that is positve by a negative number or a number that is negative by a positive number (same thing), the product/answer will always be a negative number. But when you multiply/divide a positive number by positive or negative by negative, the product/answer will always be positive number E.g:

-2 x 2= -4 / 2 x (-2)= -4

-2 -:- 2= -1 / 2 -:- (-2)= -1

E.g:

2 x 2=4 / -2 x (-2)=4

2 -:- 2= 1 / -2 -:- (-2)=1