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The Cuisenaire Gattegno Method Of Teaching Mathematics

If the two blue rectangles (2 × 5 × 9) are subtracted from this total area, the pink square (42) remains. In writing this would be 92 + 52 – 2 × (5 × 9) = 42 When (9 – 5)2 is written instead of its equivalent 42, the equation then becomes (9 – 5)2 = 92 + 52 – 2 × (5 × 9) Once demonstrated, the exercise must be repeated using other rods; for example: 42 = (10 – 6)2 32 = (7 – 4)2 52 = (8 – 3)2 Pupils should then be able to apply the idea confidently to such squares as

and

292 = (30 – 1)2 = 302 + 12 – (2 × 30 × 1) = 900 + 1 — 60 = 841 172 = (20 – 3)2 = 202 + 32 – (2 × 20 × 3) = 400 + 9 – 120 = 289

As a result of the foregoing exercises with squares, pupils are equipped, as for multiplication generally, with the widest variety of methods for finding squares. Thus: 282 = 28 × 28 = 42 × 72 = (25 + 3)2 = (30 — 2)2

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The Cuisenaire Gattegno method of teaching Mathematics  

The Cuisenaire Gattegno method of teaching Mathematics

The Cuisenaire Gattegno method of teaching Mathematics  

The Cuisenaire Gattegno method of teaching Mathematics

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