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Quadratic Factorising. If you can long multiply you can factorise!. 24 x 28. (20 + 4)(20 + 8). 20. 4. 24 28 192 480 672. x. 20. 400. 80. 8 x 24. 480. +. 20 x 24. 8. 160. 32. 192. 400 80 160 32. +. 672. 1. ( a + 4) x ( a + 8). ( a + 4)( a + 8). a.
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Quadratic Factorising If you can long multiply you can factorise!
24 x 28 (20 + 4)(20 + 8) 20 4 24 28 192 480 672 x 20 400 80 8 x 24 480 + 20 x 24 8 160 32 192 400 80 160 32 + 672 1
(a + 4) x (a + 8) (a + 4)(a + 8) a 4 (a + 4) (a + 8) 8a + 32 x a a2 4a 8(a + 4) a2 + 4a + a(a + 4) a2 + 4a a2 + 12a + 32 8 8a 32 8a + 32 a2 4a 8a 32 + a2 + 12a + 32 2
(a - 4) x (a + 8) (a - 4)(a + 8) a -4 (a- 4) (a + 8) 8a- 32 x a a2 -4a 8(a- 4) a2-4a + a(a- 4) a2-4a a2 + 4a- 32 8 8a -32 8a- 32 a2 -4a 8a -32 + a2 + 4a - 32 3
(a - 4) x (a - 8) (a - 4)(a - 8) a -4 (a- 4) (a- 8) 8a + 32 x a a2 -4a 8(a- 4) a2-4a + a(a- 4) a2-4a a2-12a + 32 -8 -8a +32 -8a + 32 a2 -4a -8a +32 + a2-12a + 32 4