Operation With Signed Numbers (Understanding the Basics)

Rule1: To add two numbers having like signs, add the two numbers and prefix their common sign.

ex: 2 + 2 = 4 , we just simply add the two numbers and prefix their common sign that is, (+), the positive sign... on the other hand...

-2 +( -2) = -4, here we also add the numbers and again we just prefix the common sign.

Rule2: To add two numbers having unlike signs, find the difference of the two numbers and prefix the sign of the bigger number...

ex: -3 + 4 = 1 , the difference of the two number is 1 and since 4 is the bigger number, its sign should be used in the answer.

-5 + 2 = -3 , as you see that the carrier of the (-) sign is the bigger number, so it will be the sign of the answer.

Rule3: To multiply two numbers having like signs, the answer is always a (+) sign carrier.

ex: 2 x 2 = 4 ; -3 x (-3) = 9

Rule4: To multiply two numbers having unlike signs, the answer is always (-) sign carrier.

ex: -3 x 4 = -12 ; 3 x -4 = 12

Rule5: To divide two numbers having like/ unlike signs, just do the same with rule3 and rule4 respectively.

ex: -9/-3 = 3 ; 9/-3 = -3

9/3 = 3 ; -9/3 = -3