Question

which number line represents the x - axis when it is extended?
which number line represents the y - axis when it is extended?

Explanation:

Step1: Analyze the \(y\) - axis properties

The \(y\) - axis is a vertical number line. Positive values are above \(0\) and negative values are below \(0\). The scale should be consistent.

Step2: Check each option

• First option: The values below \(0\) are incorrect (should be negative).
• Second option: The values below \(0\) are incorrect (should be negative).
• Third option: The values are not in the correct order (e.g., \(- 1\) should be above \(-2\) etc.).
• Fourth option: This number line has \(0\) in the middle, positive values (\(1\)) above \(0\) and negative values (\(-1,-2,-3,-4,-5\)) below \(0\) in the correct order.

Answer:

The fourth number line (with \(0\) in the middle, \(1\) above \(0\) and \(-1,-2,-3,-4,-5\) below \(0\)) represents the \(y\) - axis when extended.