Trial & Improvement
This spreadsheet activity allows pupils to refine the solution of an equation of the form ax2 ± cx = n by trial and improvement.

The resource includes
  • An interactive Excel spreadsheet
  • Instructions for using the spreadsheet
  • Lesson notes for teachers
Pupils use systematic trial and improvement methods and ICT tools to find approximate solutions to equations such as x2 + x = 20. The spreadsheet accepts as correct answers accurate to three decimal places.

The activity allows pupils to try to refine a solution to an equation of the form ax2 ± cx = n by trying different values of x. The equation can be changed to cater for a range of prior knowledge. The activity encourages thinking about the effects on the solution of changing the value of x.

The activity provides opportunities for:
  • whole class teaching
  • paired work
  • oral work as pupils justify subsequent attempts in the light of previous outcomes.
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