Terminology & Notations MCQs Quiz | Class 9

This Class IX Mathematics (Code 041) quiz focuses on Unit III: Coordinate Geometry. It covers quadrant naming, sign conventions, and plotting rules to test your understanding of the Cartesian plane. Complete the 10 MCQs below and click Submit to check your score and download the PDF answer key.

Coordinate Geometry: Key Concepts

Coordinate Geometry provides a connection between algebra and geometry through graphs of lines and curves. In Class 9, we focus on the Cartesian system, which allows us to locate points on a plane using two perpendicular lines.

1. The Cartesian Plane

The system consists of two number lines intersecting at right angles:

  • x-axis: The horizontal number line.
  • y-axis: The vertical number line.
  • Origin (O): The point of intersection of the two axes. Its coordinates are always (0, 0).

2. Quadrants and Sign Convention

The axes divide the plane into four parts called quadrants. The numbering starts from the top-right and moves anti-clockwise.

Quadrant x-coordinate y-coordinate Sign Structure
Quadrant I Positive (+) Positive (+) (+, +)
Quadrant II Negative (-) Positive (+) (-, +)
Quadrant III Negative (-) Negative (-) (-, -)
Quadrant IV Positive (+) Negative (-) (+, -)

3. Terminology

  • Abscissa: The x-coordinate of a point (distance from the y-axis).
  • Ordinate: The y-coordinate of a point (distance from the x-axis).
  • A point on the x-axis has the form (x, 0).
  • A point on the y-axis has the form (0, y).

4. Quick Revision Points

Remember that the order matters: (x, y) is not the same as (y, x) unless x equals y. Always plot the x-value first by moving horizontally, then the y-value by moving vertically.

5. Extra Practice Questions

  1. Find the coordinates of a point whose abscissa is -5 and ordinate is 3.
  2. In which quadrant does the point (-2, -8) lie?
  3. What is the perpendicular distance of the point (4, 5) from the y-axis?
  4. If a point lies on the x-axis at a distance of 4 units to the left of the origin, what are its coordinates?
  5. Write the equation of the x-axis. (Hint: y = 0)