In this topic adding two numbers we have given some of the rules.This will be very useful to school students and beginners of math.

Whenever we are adding two integers with different signs we have to consider the symbols first if both symbols are same like "++" and "--" we have to add both the numbers and we have to put the same symbol for the answer also. If we have different symbols like "+-" or "-+" for both the numbers we have to subtract them and we have to put the large number symbol to the answer. We have given these rules in the below table.Students should practice this well to do simplification fast.

In adding two numbers we have four rules

Sign of first number Sign of Second number what we have to do Sign of answer
Positive
Positive
Positive
Negative
Negative
Negative
Positive
Negative
Subtract
Sign of big number
Negative
Positive
Subtract
Sign of big number

The following image describes adding two numbers which are both negative. Consider the below examples for understanding those concepts clearly.

Example 1:

Simplify -51 + 23

Solution:

Step 1: We have different signs for both the numbers.So we have to subtract them.

Step 2: So the given numbers should be rearranged as 23-51.

Step 3: Finally the answer should be -28

Example 2:

Simplify -11 - 13

Solution:

Step 1: We have same signs for both the numbers.So we have to add them.

Step 2: So the answer should be -24

Example 3:

Simplify 51 + 23

Solution:

Step 1: We have same signs for both the numbers.So we have to add them.

Step 2: So the answer should be 74

Example 4:

Simplify 17 - 5

Solution:

Step 1: We have different signs for both the numbers. That is we are having positive sign for the first number 17 and negative symbol for the the second number that is 5. To simplify this we have to subtract them and we have to put the symbol of greater number to the answer.

Step 2: So the answer should be 12

Students can try to do the practice problems on their own using the method discussed in the above examples. If you are having any doubt you can contact us through mail, we will help you to clear all your doubts.

Practice problems: 