Theory:

A number line is defined as a straight line with numbers placed at equal interval along its length. It is usually represented horizontally, and it can be extended infinitely in any direction.
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Visualising the integers on the number line is pretty easy when compared to the numbers with more decimal expansion.
Example:
We can locate the integers directly on the number line.
 
Suppose we want to locate point \(6\) on the number line, then we can mark it as follows:
 
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