9A Aim 53 ­ factoring trinomial.notebook
Aim #53: How do we factor quadratic trinomials?
Do Now: Multiply: (x + 5)(x + 2)
2
Factor: x + 7x + 10
How can we check if we factored correctly???
Multiply: (2x + 1)(x - 4)
2
Factor: 2x - 7x - 4
Factor 3x2 + 14x - 5
)(x
(3x
3x
2
)
(3x - 1)(x + 5)
-5
(3x - 1)(x + 5)
-1x
15x
14x
1
9A Aim 53 ­ factoring trinomial.notebook
Keep the following arithmetic rules
in mind while factoring:
(+ ) + ( + ) = +
(- ) + ( - ) = (+) + (-) = takes the sign of the bigger one
(+)(+) = +
(-)(-) = +
(+)(-) = -
Factor
1. x2 - 7x + 12
2. 3x2 + 5x + 2
3. x2 - 6x - 7
4. 5x2 + 34x - 7
.
Let's sum it up!!!
When we factor a trinomial we need to find
*factors that multiply to the first term
*factors that multiply to the last term
*when we distribute, the middle terms have to add to
the middle term of the trinomial
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