**INTEGERS**

**Integer **is any number in the number line which is a whole number not including fraction. It includes 1, 2, 3,… and their opposite signs, -1,-2,-3,… including 0. Integers are signed numbers, negative(-1) and positive (+). When a number; say 2 is given, it is written as +2 or 2, without a sign is considered as positive. A negative number say negative 2 is written as -2.

In other words, the **positive integers** are the counting numbers,: 1,2,3,… on the right of 0 or at the x –axis in the coordinate system, whereas, the **negative integers** are those numbers opposite sign. Going to the right of the x-y axes coordinate system indicates positive, going to the left indicates negative. Going up of at the y coordinate indicates positive, and going down of the coordinate axis indicates negative sign.

The x-y Coordinate system

Pic Source: https://magoosh.com/hs/sat/sat-math/sat-math-strategies/2014/coordinate-geometry-basics/

**Integers in reality**

Positive |
Negative |

Adding how many | Deducting points |

Deposit money in bank | Withdrawing money from bank |

Earning money from somewhere | Borrowing money from anywhere |

Winning at any case | Losing at any case |

Increasing or Incrementing | Decreasing or devaluating |

Going to the east | Going to the west |

Going up an elevator | Going down at an elevator |

Swimming up from the ocean | Diving into the ocean |

Airplane flying up in the sky | Submarine sailing in the deep ocean |

Rising of temperature at any time | Freezing of temperature at any time |

Standing taller | Bowing down to sit down |

**Operations in Integers: Addition and Subtraction**

- – 4 + 11 = 7
- – 4 + (+11) = 7
- 4+11= 15
- +4 + (+11) = 15
- -20 + 6 = -14
- – 50+-13 = – 63
- -1+ – 99 = – 100
- 1+99 = 100
- 37 + -2 = 35
- -2 + – 3 = – 5

Important Rule to Use:

Adapt the lyrics from the song tune of the song: Row, row your boat:

* Same sign, add and keep, *

* Different sign, subtract*

* Take the sign of the bigger number*

* Then you will be exact *

Click on the link below to play:

Subtraction and Addition Rule of Integers

**Word Problems:**

1. Mr. Mishra deposited 10,000 dollars and withdrew 2000 dollars a week after. How much money remained to his bank account?

Solution: $10000 + ( – 2000) = $8,000 or

$10000 – 2000 = $8,000 remaining amount

2. Pao dives 2 meters down the ocean from a view deck of 5 meters above sea level, then swam a bit level up of a meter. How deep is his current position from the sea level?

Solution: -2 + 5 + 1 = 4 or

5 +(-2) + (1) = 4m

3. Susie borrowed 1 baht today and borrowed 9 baht a day after from her friend. How much money Susie owed in total?

Solution: -1 + -9 = -10 (follow subtraction rule)

4. Susie owed 10 baht from friend and returned 5 baht today, how much does she still owe her friend?

Solution: -10 – (+) 5 = – 5

+ – if the operation is subtraction,

change the subtraction sign to addition

and change sign of the subtrahend, then proceed to addition rule

Have a nice day!

## Comments

A quick review guide on Integers for Pakpoom, Grade 7 student at SWU, Thailand.

Good luck.

t.ramz you are very good

to teach me

Pls make it short

yessssssssss