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2.1 – Integers & The Number Line
 Numbers such as 3 (read “positive three” or just “three”) and  3 (read
“negative three”) that are the same distance from 0, but on opposite sides
of 0, are called opposites.
 Zero is its own opposite.
 The set of integers consists of the whole numbers and their opposites.
 On the number line, the positive integers are to the right of 0, and the
negative integers are to the left of zero.
 Zero is neither positive nor negative.
Definition
The set of integers consists of the positive integers, negative integers, and
zero. ...  4,3,2,1,0,1,2,3,4,...
 We use the symbol < to mean is less than. For example, 6  8 means “6
is less than 8.”
 The symbol > means is greater than. For example, 2  4 means “2 is
greater than  4 .”
 The symbols > and < are called inequality symbols.
 A mathematical sentence that contains an inequality symbol is called an
inequality.
Example 1 – Insert the proper symbol, < or >, to get a true statement.
a. 8
128
d. 14
 814
b. 13
713
e.  10
 5  10
c.  5
75
f.  4
 11 4
 The absolute value of a number is its distance from 0 on the number
line.
 We use the symbol n to represent “the absolute value of n.”
 The absolute value of a number is either positive or zero.
Example 2 – Find the absolute value.
a. 3
b.  3
c. 0
L11 – pg 57 (11, 15, 19, 23, 29 & 43-51 odd)
d.  27