Quadratic Equations Formulas CBSE Class 10 Maths
Quadratic equations for Class 10 form a fundamental part of the CBSE Mathematics curriculum and assess a student’s understanding of algebraic concepts. A quadratic equation involves a second-degree polynomial and helps students find unknown values, identify the nature of solutions, and solve exam-oriented problems accurately. A clear understanding of how formulas work and how to apply them in different situations allows students to solve quadratic equations correctly and avoid common errors. In this blog, you will get to know the key quadratic equations formulas, how to use them to find roots, and how these formulas apply across different types of Class 10 problems. Important Quadratic Equations Formulas Class 10 Standard Form of a Quadratic Equation A quadratic equation represents a second-degree polynomial written as: ax² + bx + c = 0, where a ≠ 0 Here, a, b, and c are real numbers. The value of a controls the degree of the equation and confirms it as quadratic. Roots of a Quadratic Equation A real number α becomes a root of the equation ax² + bx + c = 0 when it satisfies the condition: aα² + bα + c = 0 If this equality holds true, then x = α solves the quadratic equation. Methods Used to Solve Quadratic Equations Factorisation Method This method works when the quadratic expression splits into two linear factors. After factorisation, equate each factor to zero to find the roots. Best used when coefficients remain small and factor pairs exist clearly. Completing the Square Method This approach converts a quadratic expression into a perfect square by rearranging terms. Key identities used: Quadratic Formula When the discriminant value stays zero or positive, the roots follow this formula: x = (−b ± √(b² − 4ac)) / 2a Discriminant of a Quadratic Equation The discriminant determines the type of roots and is defined as: D = b² − 4ac It provides immediate insight into the nature before solving the equation fully. Nature of Roots Based on Discriminant For the equation ax² + bx + c = 0: Quadratic Equation from Given Roots If the sum and product of roots are known, form the equation as: x² − (sum of roots)x + (product of roots) = 0 Sum and Product of Roots For the equation ax² + bx + c = 0: Applications of Quadratic Equations Class 10 Quadratic equations model situations where values follow a curved or changing pattern. Tips to Learn Quadratic Equations Class 10 Example Example 1: Find the discriminant of the quadratic equationx² − 4x + 5 = 0 and state the nature of its roots. Solution: The given equation follows the form ax² + bx + c = 0, wherea = 1, b = −4, and c = 5. The discriminant isD = b² − 4acD = (−4)² − 4(1)(5)D = 16 − 20D = −4 < 0 Since the discriminant is less than 0, the quadratic equation has no real roots.







