You can use this dynamic worksheet to have students explore and discover the procedure of completing the square for solving quadratic equation of the form x2+bx=c. Note that because area is used to visualise the product of the factors, the value of b cannot be negative. You can give them problems where b is negative after they have discovered the procedure. Teaching algebra with geometrical representation is one way of scaffolding students’ understanding of algebra.
Suggested sequence of tasks:
1. Solve the following quadratic equations using the worksheet.
2. Make your own equations and solve them using the worksheet.
3. Think of a way of solving the quadratic equation (e.g. x2+8x=3) algebraically. That is, without using of the area model.
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