Quadratic Equations

CBSE Board Exam Blueprint & Topic Weightage: Quadratic Equations

In the Class 10 CBSE Board Examination, Quadratic Equations is a core component of Unit 2: Algebra, consistently carrying 5 to 6 marks in the annual 80-mark written board paper. Recurring question formats observed over past board papers include:

• Section A (1 Mark MCQ): Identifying whether an equation is quadratic, evaluating the discriminant \(D = b^2 - 4ac\), or determining the nature of roots for given values of parameter \(k\).
• Section B / C (2 or 3 Marks): Solving quadratic equations by factorisation (splitting the middle term) and applying the quadratic formula \(x = \frac{-b \pm \sqrt{b^2-4ac}}{2a}\) to solve radical and fractional equations.
• Section D / E (4 to 5 Marks): Challenging word problems on train speeds (train travelling at uniform speed taking less time if speed increased), water taps filling a tank together, and geometric dimensions.

Key Revision Tips & Common Pitfalls

When questions state that a quadratic equation has real and equal roots, set \(D = b^2 - 4ac = 0\) and solve for the unknown parameter. Check for extraneous roots in fractional equations by ensuring denominators are non-zero. Clearly specify units (km/h, hours, meters) in final answers for word problems.