Mathematics for IGCSE & O level - Algebraic Manipulation (Section 4 - No. 23)
Which strategy is best to employ when the coefficient of the x² term is not 1?
Trial and error
Factoring by grouping
Completing the square
Difference of squares
Uitleg
When a is not 1, trial and error is more difficult, however, factoring by grouping and completing the square are still great methods.