Class 9 Maths — Chapter 3: COORDINATE GEOMETRY
Chapter 3: COORDINATE GEOMETRY is a chapter in Class 9 Maths (NCERT), part of the CBSE NCERT curriculum followed by over 25 million students across India. This chapter covers 6 topics including The Need for a Coordinate System, The Cartesian System, Coordinates of a Point: Abscissa and Ordinate. BrainWeave provides free AI-powered explanations — by voice or text, in Hindi or English — with no signup required.
What you'll learn
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▸The Need for a Coordinate Systempositionplanereference lineslocating pointstwo dimensions
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▸The Cartesian SystemCore conceptCartesian planex-axisy-axisorigincoordinate axes
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▸Coordinates of a Point: Abscissa and OrdinateCore conceptcoordinatesordered pairabscissaordinate(x, y)
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▸Quadrants and Sign ConventionsCore conceptquadrantsign conventionQuadrant IQuadrant IIpositive/negative
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▸Plotting Points in the Cartesian PlaneCore conceptplottinggraphlocatemarkCartesian coordinate system
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▸Coordinates of Points on the AxesCore concepton the x-axison the y-axisorigin coordinates(x, 0)(0, y)
Chapter Summary
Understanding why two independent pieces of information (like distance from two perpendicular lines) are required to precisely locate a point or object in a plane. This is illustrated with real-world examples like seating plans and street maps.
The formal system for locating points in a plane, developed by René Descartes. It consists of two perpendicular number lines, the x-axis (horizontal) and the y-axis (vertical), intersecting at a point called the origin.
Understanding that the position of any point in the Cartesian plane is represented by an ordered pair of numbers (x, y). The x-coordinate is called the abscissa, and the y-coordinate is called the ordinate.
Learning how the coordinate axes divide the plane into four regions called quadrants. Students must know the sign (+ or -) of the abscissa and ordinate in each of the four quadrants (e.g., Quadrant I is (+,+), Quadrant II is (-,+), etc.).
The practical skill of marking the position of a point on the Cartesian plane when its coordinates (x, y) are given. This involves moving along the x-axis for the abscissa and then parallel to the y-axis for the ordinate.
Identifying the coordinates of points that lie directly on the x-axis or the y-axis. This includes understanding that any point on the x-axis has coordinates (x, 0) and any point on the y-axis has coordinates (0, y). The origin is at (0, 0).
Practice Questions from this Chapter
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- Explain map coordinates simply. Get Solution →
- Compare latitude with longitude. Get Solution →
- Apply coordinates in daily life. Get Solution →
- Who is credited with developing the system of describing the position of a point in a plane, also known as the Cartesian system? Get Solution →
- What is the horizontal line in the Cartesian coordinate system called? Get Solution →
- What is the vertical line in the Cartesian coordinate system called? Get Solution →
- What is the name for the point where the x-axis and the y-axis intersect? Get Solution →
- The coordinate axes divide the plane into four parts. What are these parts called? Get Solution →
Did you know?
- 💡 René Descartes invented coordinate geometry after watching a fly on his ceiling.
- 💡 Ancient Babylonians used a form of coordinate system for astronomy over 3000 years ago.
- 💡 GPS satellites use precise coordinate geometry to locate any spot on Earth.
- 💡 The famous Battleship game uses coordinates to locate and sink enemy ships.
- 💡 A point's position in space can also be described with three coordinates, not just two.
Frequently Asked Questions
How many topics are covered in this chapter?
This chapter covers 6 key topics: The Need for a Coordinate System, The Cartesian System, Coordinates of a Point: Abscissa and Ordinate, Quadrants and Sign Conventions, Plotting Points in the Cartesian Plane, and more. The BrainWeave AI tutor explains each one with examples.
Is Chapter 3: COORDINATE GEOMETRY important for board exams?
Class 9 is a foundation year. Mastering this chapter now will help you build strong fundamentals for the higher classes.
Can I get NCERT solutions for this chapter in Hindi?
Yes. BrainWeave's AI tutor supports Hindi, English, and Hinglish for both voice and text chat. Just ask your question in your preferred language.
Is BrainWeave free for Class 9?
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Can I use voice chat for this chapter?
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