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When factoring easy trinomials When factoring easy trinomials x2 - 8x + 12 We use the last sign to know... When factoring easy trinomials x2 - 8x + 12 last sign whether the factor signs are the same We use the last sign to know... When factoring easy trinomials x2 - 8x + 12 last sign whether the factor signs are the same ( x + ) ( x + ) ( x - ) ( x - ) We use the last sign to know... When factoring easy trinomials x2 - 8x + 12 factor signs the same last sign whether the factor signs are the same ( x + ) ( x + ) ( x - ) ( x - ) We use the last sign to know... When factoring easy trinomials x2 - 8x + 12 last sign or different whether the factor signs are the same ( x + ) ( x + ) ( x - ) ( x - ) We use the last sign to know... When factoring easy trinomials x2 - 8x + 12 different signs last sign or different ( x - ) ( x + ) ( x - ) ( x + ) ? x2 + 5x - 2 Match the trinomial with the correct factor signs ( x - ) ( x - ) ? x2 - 5x + 2 ( x + ) ( x + ) ? x2 + 5x + 2 x2 - 6x + 8 When the last sign is positive x2 - 6x + 8 positive sign previous sign then we use the previous sign to determine When the last sign is positive what are signs will be x2 - 6x + 8 So we know the factor signs are previous sign then we use the previous sign to determine When the last sign is positive what are signs will be x2 - 6x + 8 So we know the factor signs are previous sign then we use the previous sign to determine When the last sign is positive what are signs will be ( x - ) ( x - ) x2 - 6x + 8 ( x - ) ( x + ) Match the factor signs with the correct trinomial x2 - 2x - 1 ? ( x + ) ( x + ) x2 + 2x + 5 ? ( x - ) ( x - ) x2 - 2x + 5 ? The last sign also tells us... x2 - 6x + 8 last sign The last sign also tells us... ...whether we... x2 - 6x + 8 last sign The last sign also tells us... ...whether we... ...add or subtract... x2 - 6x + 8 last sign The last sign also tells us... ...whether we... ...add or subtract... x2 - 6x + 8 ...our factors. last sign The last sign also tells us... ...whether we... ...add or subtract... Let's explain. x2 - 6x + 8 ...our factors. last sign First, list all the factors of 8... x2 - 6x + 8 First, list all the factors of 8... 1 and 8 x2 - 6x + 8 First, list all the factors of 8... What do you multiply 4 by to get 8? 1 and 8 2 and 4 x2 - 6x + 8 First, list all the factors of 8... then we look at our last sign 1 and 8 2 and 4 x2 - 6x + 8 First, list all the factors of 8... then we look at our last sign 1 and 8 2 and 4 x2 - 6x + 8 last sign First, list all the factors of 8... then we look at our last sign since the last sign is a positive 1 and 8 2 and 4 x2 - 6x + 8 positive we want to ADD those factors to get the middle number First, list all the factors of 8... then we look at our last sign since the last sign is a positive 1 and 8 2 and 4 x2 - 6x + 8 positive we want to ADD those factors to get the middle number First, list all the factors of 8... then we look at our last sign since the last sign is a positive the middle number is 6 1 and 8 2 and 4 x2 - 6x + 8 middle number we want to ADD those factors to get the middle number First, list all the factors of 8... then we look at our last sign since the last sign is a positive the middle number is 6 1 and 8 2 and 4 x2 - 6x + 8 1 + 8 ≠ 6 middle number we want to ADD those factors to get the middle number First, list all the factors of 8... then we look at our last sign since the last sign is a positive the middle number is 6 1 and 8 2 and 4 x2 - 6x + 8 1 + 8 ≠ 6 middle number we want to ADD those factors to get the middle number First, list all the factors of 8... then we look at our last sign since the last sign is a positive the middle number is 6 1 and 8 2 and 4 x2 - 6x + 8 1 + 8 ≠ 6 2 + 4 = 6 middle number we want to ADD those factors to get the middle number First, list all the factors of 8... then we look at our last sign since the last sign is a positive the middle number is 6 1 and 8 2 and 4 x2 - 6x + 8 1 + 8 ≠ 6 2 + 4 = 6 middle number So 2 and 4 are my factors 1 and 8 2 and 4 x2 - 6x + 8 1 + 8 ≠ 6 2 + 4 = 6 and since I already know my factor signs So 2 and 4 are my factors 1 and 8 2 and 4 x2 - 6x + 8 1 + 8 ≠ 6 2 + 4 = 6 and since I already know my factor signs ( x - ) ( x - ) So 2 and 4 are my factors 1 and 8 2 and 4 x2 - 6x + 8 1 + 8 ≠ 6 2 + 4 = 6 and since I already know my factor signs ( x - ) ( x - ) So 2 and 4 are my factors 1 and 8 2 and 4 x2 - 6x + 8 I just plug in my factors 1 + 8 ≠ 6 2 + 4 = 6 and since I already know my factor signs ( x - 2 ) ( x - 4 ) So 2 and 4 are my factors 1 and 8 2 and 4 x2 - 6x + 8 I just plug in my factors 1 + 8 ≠ 6 2 + 4 = 6 ( x - 2 ) ( x - 4 ) x2 - 6x + 8 and that's the answer! x2 + 8x + 12 The last sign is + x2 + 8x + 12 The last sign is + so my factor signs are x2 + 8x + 12 the same different The last sign is + The previous sign is + so my factor signs are x2 + 8x + 12 the same The last sign is + The previous sign is + so my factor signs are x2 + 8x + 12 so my factor signs are both the same positive negative So I know that my factors signs look like ( x + ) ( x + ) ( x - ) ( x - ) ( x - ) ( x + ) ( x + ) ( x - ) x2 + 8x + 12 So I know that my factors signs look like I know I must ( x + ) ( x + ) x2 + 8x + 12 add factors subtract factors So I know that my factors signs look like I know I must ( x + ) ( x + ) x2 + 8x + 12 add factors to get 8 The factors of 12 are... ( x + ) ( x + ) x2 + 8x + 12 1 and 12 2 and 6 3 and 4 The factors of 12 are... ( x + ) ( x + ) x2 + 8x + 12 1 and 12 2 and 6 3 and 4 The factors of 12 are... ( x + ) ( x + ) x2 + 8x + 12 1 and 12 2 and 6 3 and 4 which one adds to get 8? So my factors are... ( x + ) ( x + ) x2 + 8x + 12 So my factors are... ( x +2 ) ( x + ) x2 + 8x + 12 |