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FACTORING TRINOMIALS 2 AX + BX + C; A = 1 Ex A) x2 + 11x + 24 Read backwards in a way – what numbers can be multiplied to give you 24 that when you add you get 11? 8 and 3 If the second sign is positive – both signs are the same. They will be what the first sign is. ( x + 3) (x + 8) X2 – 3X + 2 (x - ) (x - ) What number can you multiply to get 2 that add to give you 3? 2 and 1 (x - 2 ) (x - 1 ) X2 – 12X + 36 2X2 + 10X + 8 Ex A) x2 + 5x - 24 Read backwards in a way – what numbers can be multiplied to give you 24 that when you subtract you get 5? 8 and 3 If second sign in negative, the signs are different and the largest # goes with the first sign. ( x - 3) (x + 8) X2 – 5X – 14 X2 – 3X – 10 3X2 + 6X – 9 2x2 – 18x – 20 x 2 – 7x + 12 X2 – 6x - 27 x 2 + 20x + 51 54 – 15x + x2 72 – 17x TRY THESE! + x2 2x2 – 18x – 20 = 2(x + 1)(x - 10) x2 – 7x + 12 = (x – 3)(x – 4) x2 – 6x – 27 = (x – 9)(x + 3) x2 + 20x + 51 = (x + 17)(x + 3) 54 – 15x + x2 = (x – 6)(x – 9) 72 – 17x + x2 = (x – 8)(x – 9) TRY THESE!