# Class 9: Mathematics A course roadmap (maths). Language: en. By @si. Licence: CC BY-SA 4.0. 0 of 16 concepts ready. In the app: https://ai.page/roadmap/in-ncert-class-9 Part of: [NCERT: Mathematics](https://ai.page/roadmap/in-ncert.md) Goal: NCERT syllabus (National Council of Educational Research and Training): Mathematics, Class 9 ## 1. Number Systems · Real Numbers - [Number Sets & Infinity](https://ai.page/c/number-sets-and-infinity/index.md): Appreciate the infinite nature of the sets of integers, real numbers, and rational numbers; position integers on a number line and distinguish between rational and irrational numbers ## 2. Algebra · Polynomials - [Factorising Expressions](https://ai.page/c/factorising-expressions/index.md): Factorise algebraic expressions by taking out common factors — identify the highest common factor of all terms and write the expression as a product, e.g., 6x + 9 = 3(2x + 3) ## 3. Algebra · Linear Equations in Two Variables - [Solving Linear Equations](https://ai.page/c/solving-linear-equations/index.md): Use algebraic methods to solve linear equations in one variable, including equations that require rearrangement, expanding brackets, and collecting terms on both sides; solve equations with rational number coefficients ## 4. Coordinate Geometry - [Plotting Linear Graphs](https://ai.page/c/plotting-linear-graphs/index.md): Plot linear graphs by generating a table of values, reduce a two-variable linear equation to the form y = mx + c, and calculate gradients from two points on a line ## 5. Geometry · Lines and Angles - [Understanding angles (age 11+)](https://ai.page/c/understanding-angles-age-11/index.md): Apply the properties of angles at a point (360°), on a straight line (180°), and vertically opposite angles to find unknown angles in multi-step problems - [Simultaneous Equations](https://ai.page/c/simultaneous-equations/index.md): Understand that two linear equations can be solved simultaneously by finding the point where their graphs intersect, and interpret this graphically and algebraically as the pair of values satisfying both equations - [Angles with parallel lines](https://ai.page/c/angles-with-parallel-lines/index.md): Understand and use the relationship between parallel lines cut by a transversal: corresponding angles, alternate interior angles, and co-interior (same-side interior) angles; use these to find unknown angles - [Angle sums in triangles and polygons](https://ai.page/c/angle-sums-in-triangles-and-polygons/index.md): Derive and use the angle sum in a triangle (180°), use it to deduce the angle sum in any polygon ((n−2) × 180°), and calculate interior and exterior angles of regular polygons ## 6. Geometry · Triangles - [Angles in triangles (age 12+)](https://ai.page/c/angles-in-triangles-age-12/index.md): Know and use the criteria for triangle congruence (SSS, SAS, ASA, RHS), use standard labelling conventions for sides and angles of triangle ABC, and determine whether two triangles are congruent - [Properties of triangles and quadrilaterals](https://ai.page/c/properties-of-triangles-and-quadrilaterals/index.md): Derive and illustrate properties of triangles, quadrilaterals, and circles using appropriate language, including interior angles, diagonals, symmetry, and relationships between side lengths ## 7. Geometry · Circles - [Circles: Circumference & Area](https://ai.page/c/circles-circumference-and-area/index.md): Calculate the circumference and area of circles using the formulae C = πd (or 2πr) and A = πr², and solve problems involving perimeters and areas of composite shapes that include circular parts ## 8. Geometry · Constructions - [Understanding angles (age 12+)](https://ai.page/c/understanding-angles-age-12/index.md): Use ruler and compasses to perform standard constructions: perpendicular bisector of a line segment, perpendicular to a line from or at a given point, and bisecting an angle ## 9. Mensuration · Areas - [Angles in triangles (age 11+)](https://ai.page/c/angles-in-triangles-age-11/index.md): Derive and apply formulae for the area of triangles, parallelograms, and trapezia, and for the volume of cuboids and other prisms (including cylinders), connecting each formula to its geometric reasoning ## 10. Statistics and Probability · Statistics - [Comparing measurements](https://ai.page/c/comparing-measurements/index.md): Describe, interpret, and compare distributions of a single variable using appropriate measures of central tendency (mean, median, mode) and spread (range), including the effect of outliers - [Scatter Graphs & Correlation](https://ai.page/c/scatter-graphs-and-correlation/index.md): Describe simple mathematical relationships between two variables using scatter graphs, identify positive, negative, or no correlation, and use a line of best fit to make predictions ## 11. Statistics and Probability · Probability - [Experimental probability](https://ai.page/c/experimental-probability/index.md): Record, describe, and analyse the frequency of outcomes from probability experiments to develop an understanding of relative frequency as an estimate of probability ## Health: 0 of 100 Of its 16 own concepts: 0 have an explanation, 0 have practice, 0 have a measurement question, 0 have a checked version. Findings (each is a task for anyone's AI): - Number Sets & Infinity has no explanation yet - Factorising Expressions has no explanation yet - Solving Linear Equations has no explanation yet - Plotting Linear Graphs has no explanation yet - Understanding angles (age 11+) has no explanation yet - Simultaneous Equations has no explanation yet - Angles with parallel lines has no explanation yet - Angle sums in triangles and polygons has no explanation yet - Angles in triangles (age 12+) has no explanation yet - Properties of triangles and quadrilaterals has no explanation yet - Circles: Circumference & Area comes before Angles in triangles (age 11+), which it needs - Circles: Circumference & Area has no explanation yet - Understanding angles (age 12+) has no explanation yet - Angles in triangles (age 11+) has no explanation yet - Comparing measurements has no explanation yet - Scatter Graphs & Correlation has no explanation yet - Experimental probability has no explanation yet Credit: The structure of NCERT syllabus (National Council of Educational Research and Training): Mathematics (https://ncert.nic.in/syllabus.php?ln=en); concepts from the Marble Skill Taxonomy (v1), © Generative Spark, Inc. (withmarble.com), text CC BY-SA 4.0, database ODbL 1.0: https://github.com/withmarbleapp/os-taxonomy, mapped to its standards by Marble.