# Rules to Add Integers

### Rule 1:

When the two integers have the positive sign, add the integers and assign the (+) sign to the sum.

### For example:

Find the sum of the integers.

(i) 8 + 19 = 27

(ii) 33 + 25 = 58

(iii) 42 + 91 = 133

(iv) 59 + 87 = 146

#### Note:

Here, we have two integers having the same (+) sign. So, we add the numbers and attach (+) sign to the sum.

### Rule 2:

When the two integers have the negative sign, add the integers and assign the (-) sign to the sum.

### For example:

Find the sum of the integers.

(i) (-7) + (-9) = -16

(ii) (-23) + (-15) = -38

(iii) (-41) + (-57) = -98

(iv) (-119) + (-137) = -256

#### Note:

Here, both the integers have the same (-) sign. So, we add the numbers and attach the (-) sign to the sum.

### Rule 3:

When the two integers have opposite sign [one positive (+) and other negative (-)], find the difference of the numbers and to the difference assign the sign of the integer having greater value.

### For example:

Find the sum of the integers.

(i) (-17) + 29

= -17 + 29

[Here, two integers are with unlike signs – and +.We find the difference of the numbers is 12 and to the difference attach the sign of the integer having greater value; so the answer is positive 12].

= 12

(ii) (-81) + (+35)

= -81 + 35

[Here, two integers are with unlike signs – and +.We find the difference of the numbers is 46 and to the difference attach the sign of the integer having greater value; so the answer is negative 46].

= -46

### For example:

Find the sum of the integers.

(i) (+79) + (-57)

= 79 – 57

[Here, two integers are with unlike signs + and -.We find the difference of the numbers is 22 and to the difference attach the sign of the integer having greater value; so the answer is positive 22].

= 22

(ii) (+85) + (-121)

= 85 – 121

[Here, two integers are with unlike signs + and -.We find the difference of the numbers is 36 and to the difference attach the sign of the integer having greater value; so the answer is negative 36].

= -36

In adding integers these are the possible rules to add integers.