On the Cartesian plane, what are the horizontal number line and the vertical number line called, in that order?

Class 9Coordinate GeometryCoordinate Geometry

Step-by-Step Solution

The horizontal number line is the

x

-axis and the vertical number line is the

y

-axis. They are perpendicular and meet at the origin.

Answer: C)

x

-axis and

y

-axis

Two perpendicular axes — horizontal

(x

-axis) and vertical

(y

-axis) — meet at the **origin** (0, 0). Together they divide the plane into four **quadrants**:

- **I**:

x > 0, y

> 0 (top right)
- **II**:

x < 0, y

> 0 (top left)
- **III**:

x < 0, y

< 0 (bottom left)
- **IV**:

x > 0, y

< 0 (bottom right)

Points ON the axes don't belong to any quadrant. (a, 0) sits on the

x

-axis; (0, b) sits on the

y

-axis.

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