Factorising and solving quadratics using a grid (negative b and/or c)

Part 4 / 4 in a sequence of lessons covering solving quadratic equations by factorising.
This final lesson covers factorising (and solving) quadratics with negative coefficients using the grid method.

Sequence is:

• Part 1: Introduction to solving graphically (to build understanding that some equations have more than 1 solutions)
• Part 2: Solving factorised quadratics (undertstanding that one of the 2 linear product has to be 0 if their product is 0)
• Part 3: Factorising (and solving) monic quadratics using the grid method - when b and c are positive
• Part 4: Factorising (and solving) monic quadratics using the grid method - when b or/and c are negative
  This lesson teaches students to factorise monic quadratic equations with positive and negative coefficients using the grid method.
  It finishes by solving (as solving factorised quadratics was covered in the previous lesson).

The lesson that follows involves getting further practice by mixing monic quadratics, looking at the special cases of difference of 2 squares and perfect squares.
Grid method is very easy to use to factorise non-monic quadratic equations so this can be introduced that way too.