Year 9 Interactive Maths - Second Edition

Further Quadratic Trinomials

 7x×2 + x×1 = 14x+ x = 15x.  We reject this pair as the middle term is 9x.

The solution is read across.

Use of a Common Factor

If a quadratic trinomial has a common factor, take it out and place it in front of the brackets.  Then use the cross-multiplication method to factorise the quadratic trinomial.

Example 14

Solution:

Check:

Note:

The common factor 2 was taken out first to make the factorisation simpler.

Study Another Topic in Chapter 8: Factors

[ Factors of a Number ] [ Highest Common Factor of Algebraic Expressions ] [ Factorisation using the Common Factor ] [ Factors by Grouping 'Two and Two' ] [ Factorisation of a Difference of Two Squares ] [ Factorisation of Quadratic Trinomials ] [ Cross-Multiplication Method ] [ Further Quadratic Trinomials ] [ Use of Perfect Squares ] [ Symbols ] [ Index ]