Class 9th CBSE

Congruence of Triangles * Two triangles are congruent, if the sides and angles one triangle are equal to corresponding sides and angles of the other triangle. * There is one-to-one correspondence between the vertices f two congruent triangles ABC and XYZ such that A ↔ X, B ↔ Y and C ↔ Z. * Two ... Read more

Introduction to Lines and Angles Line Segment: A line with two end Points Ray: a line with one end point. Collinear points: If three or more points lie on the same line they are collinear. Angle: The figure formed by two rays having a common end point. Acute Angle: An angle whose measure is more ... Read more

Introduction to Euclid’s Geometry Euclid’s Definitions Definition 1: A point is that which has no part. Definition 2: A line is breathless length. Definition 3: The ends of a line are points. Definition 4: A straight line is a line which lies evenly with the points on itself. Definition 5: A surface is that which ... Read more

Introduction to Linear Equations in Two Variables * A linear equation in two variables is of the form ax + by + c = 0 Where a, b, c are real numbers and a ≠ 0, b ≠ 0. * An ordered pair (x, y) can be considered as solution if it satisfies the equation. ... Read more

Cartesian Plane The Cartesian plane, named after the mathematician “Rene Descartes”, is plane with a rectangular coordinate system that associates each point in the plane, with an ordered pair (x, y). In an ordered pair (x, y): * x is called the x-coordinate or abscissa. * y is called the y-coordinate or ordinate. Any point ... Read more

Polynomials in One Variable The general form of a polynomial in one variable is represented as p(x) = a_{n} x^{n} + a_{n - 1} x^{n - 1 } + .... a_{1} x^{1} + a_{0} Where: * a_{n} , a_{n - 1} , .... , a_{1} , a_{0} are real numbers, * The exponents of each terms ... Read more

Natural Numbers Counting numbers 1,2,3,4.... are called natural numbers and the collection of natural numbers is denoted by N. Whole Numbers Zero along with the natural numbers represent whole numbers and the collection of Whole number is denoted by ‘W’. Integers Integers are collection of positive and negative numbers including zero and the collection of ... Read more