1. 6.4 and 6.5 Factoring Trinomials
“Using Bottom’s Up Method”

2. The X factor To begin factoring trinomials draw a BIG X
East and West multiplied together = North
East and West added together =South
North
East
West
South

3. The X Factor
Do the worksheet

4. The X Factor: How to put a trinomial in the X
Make sure the polynomial is in descending order: ax² +bx +c
If ax² is – factor out a -1 before you begin
If there is a common factor, factor it out before you begin to put it in the X
Multiply a and c to get the North term
Write b in the South
Find what two numbers add to get the south and multiply to get the north. Those two numbers are your east and west

5. - - + + - + - - + - - + - + + + X Factor: 4 Options Larger # Larger #
Smaller # -
Smaller # + - +

6. The X Factor: With Trinomials
Worksheet

7. Bottom’s Up Factor out a common factor Draw your X and do the X Factor
Make East an d West your binomials
(x + west) (x + East)
Divide West and East by the # in front of x²
5. Simplify (reduce fraction)
6. Bring the bottom number up in front of x

8. See Examples