- Chinese method is really just rote learning.
- Grid method is promoted in primary schools.
- Good because it can be introduced by counting the number of squares, so promotes understanding of the size of a multiplication problem.
- For example: 14 x 12

Total = 100 + 40 + 20 + 8 = 168

- You can also expand brackets using the grid method:
- 32 x 41 is equivalent to (30 + 2) (40 + 1)
- (x + 2)(x + 1)

So the answer is x^{2} + 3x + 2

- This can be extended to negative numbers, but you need to make clear that the operations are the same.
- N.B. Students will tend to say 2x rather than x
^{2}. Scaffold using: 2×2=2^{2}, 3×3=3^{2}, 4×4=4^{2} - You can also use the grid method to explore the difference of two squares (but its even better using geogebra!)

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