Arithmetic/The Number Line

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The number line is a one-dimensional graph to show the relative positions of numbers. As you can see, as the line goes left, the numbers become smaller; as the line goes right, the numbers become larger. The line continues infinitely (without end) in both directions.

As you can see, the positive and negative numbers are of equal distance from the number zero. The distance of a number from zero is called the absolute value. The absolute value of a number is always positive or zero. It is represented by two lines on the left and right of a number.

• |-5| = 5
• |0| = 0
• |5 + 3| = |8| = 8