What are the rule when addding, subtracting, multiplying and dividing positve and negative numbers?

Question

I need help with understanding the rules when adding, subtracting, multiply or dividing positive or negative numbers.

Answer 1

A-(-B) is the same as A+B; -A-B is the same as -(A+B), in other words, add A and B and put a minus in front of the result.

(-A)*B=A*(-B)=-(A*B); A/(-B)=(-A)/B=-(A/B); (-A)/(-B)=A/B.

A-B=-(B-A) so 4-7 is the same as -(7-4)=-(3)=-3.

-A(B-C)=-A*B+AC or A*C-A*B.

Golden Rule: two minuses together make a plus! Two pluses together always make a plus.