The document discusses integers and related concepts: 1. It defines integers as whole numbers, zero, and negative numbers, and gives examples of situations involving positive and negative integers. 2. It describes the integer set Z as including all integers from negative infinity to positive infinity. Absolute value is defined as the number without its sign. 3. Examples are given of representing integers on a number line and calculating the absolute value of integers. Exercises are provided to practice these concepts.

1. Moira Clemente Alpresa IES Maestro Diego Llorente (Los Palacios y Villafranca) Integers

2. VOCABULARY Integers Whole numbers Number line Absolute value Opposite

3. 1.-Positive and negative numbers There are many situations in which you need to use numbers below zero. Examples: The height of Mount Everest is 8700m +8700 A submarine which is sailing 700 m below sea level -700 The second floor of a subterranean garage -2 He has saved 5000 € in his bank account +5000 He is 400 € overdrawn -400 The average summer temperature here is 35ºC +35 The temperature in Siberia has risen 25ºC below zero -25

4. Exercise 1 Write with an integer the following informations: The plane is flying at 9500 m high The minimum temperature yesterday was 3 degrees below zero The garage is on the second cellar The diver is swimming 20 metres deep Sergio owes 25 euros Pythagoras was born on 582 BC Solution: a)+9500m b) -3ºC c)-2 d)-20 e)-25€ f)-582

5. 2.- The integers set The integer set is formed by the natural numbers, zero and negative numbers. It is represented by Z. Z = {........., -4, -3, -2, -1, 0, 1, 2, 3, 4, ............} The integer set doesn't have a beginning or an ending and it has infinite elements. If a number is written without a sign then it is positive.

6. 2.1.Graphical representation Integers can be represented on the number line Exercise 2: Represent on a line the following numbers: -1, +3, +7 and -5

7. 2.2. Absolute value The absolute value of an integer is the number without the sign. It is represented as |a| and it is called absolute value of a. Examples: |6| = 6 |-10| = 10 |0| = 0 |123| = 123 |-3404| = 3404

8. Exercises Exercise 3:Work out the absolute value of these numbers a) |-9| b) |+5| c) |-3| d) |+7| e) |0| Solution: a) 9 b)5 c)3 d)7 e)0 Exercise 4:Find out the number that has an absolute value of 7 and is between –8 and -6 Solution: -7

9. Thanks for your attention