Quadratic Equations

Success Criteria

At the end of this chapter, students are able to:

  1. (Method 1) Solve Quadratic Equations by Factorisation.

  2. (Method 2) Solve Quadratic Equations by Completing-the-Square.

  3. (Method 3) Solve Quadratic Equations by the Quadratic Formula.

  4. Sketch the graphs of quadratic equations.

  5. Plot the graphs of quadratic equations.

  6. (Method 4) Solve Quadratic Equations by Graphical Method.

  7. Solve fractional equations by expressing them as quadratic equations.

  8. Simplify a Quadratic Expression using the substitution method (AO2).

  9. Formulate a quadratic equation from a given context (AO2).

  10. Explain the errors behind common algebraic mistakes (AO3).

Introduction

Recall that we have learnt about quadratic expressions in Secondary 2.

1) What is a Quadratic Expression?

2) How to convert an Quadratic Expression from the standard form to the factorised and vice versa using Algebraic Expansion and Factorisation.