Теория:

Integers are the set of positive and negative numbers and zero. Even whole numbers are integers. Usually for better understanding integers are represented in a number line. Negative numbers will be on the left side of the number line, and positive numbers will be on the right side of  the number line.
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Example:
The examples of negative integers are \(-1, -2, -2199\).
 
The examples of positive integers are \(1, 38, 48, 122\).
 
The number \(0\) is neither negative nor positive.
Negative numbers are always lesser than zero and positive numbers.
1)3<02)311<03)210>510004)200<500
 
Reflection of a number:
Reflection of a number will have the same absolute value as that number but with a different sign.
(Reflection of a number will be = −(absolute value of the number)
Example:
Reflection of \(-1\) is \(-(-1) = +1\)
Reflection of \(20\) is \(-20\)
The distance between the positive number and zero in a number line will be equal to the distance between the reflection of the same negative number and zero.
Distancebetween (x) and0innumberline  = Distancebetweenxand0inanumberline.
Example:
Let us take a number \(+1\) its distance in the number line from \(0\) is \(1\).
Reflection of \(+1\) will be \(-(1)\) and its distance in the number line from \(0\) is also \(1\).
Distance between \(-20\) and \(0\) is \(20 =\) Distance between \(20\) and \(0\).
 
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Important!
Numbers with decimals \((0.21, 2.35)\), Irrational numbers \(π≈3.14\), \(square\) \(roots - √2,√3\) are not integers.