1. Factor by Grouping
Skill 55

2. Objective
HSA-SSE.1a: Interpret parts of an expression such as terms, factors, and coefficients.

3. You can factor polynomials of higher degrees using grouping methods.

4. Example: Factoring by Grouping
Factor: x3 – x2 – 25x + 25.
(x3 – x2) + (–25x + 25)
Group terms.
Factor common monomials from each group.
x2(x – 1) – 25(x – 1)
(x – 1)(x2 – 25)
Factor the common binomial (x–1).
(x – 1)(x – 5)(x + 5)
Factor the difference of squares.

5. Example; Factor by Grouping
Factor: x3 – 2x2 – 9x + 18.
(x3 – 2x2) + (–9x + 18)
Group terms.
Factor common monomials from each group.
x2(x – 2) – 9(x – 2)
(x – 2)(x2 – 9)
Factor the common binomial (x–2).
(x – 2)(x – 3)(x + 3)
Factor the difference of squares.

6. Do It Yourself: Example; Factor by Grouping
Factor: 2x3 + x2 + 8x + 4.
(2x3 + x2) + (8x + 4)
x2(2x + 1) + 4(2x + 1)
(2x + 1)(x2 + 4)
(2x + 1)(x2 + 4)

7. 55: Factoring by Grouping
Questions?
Summarize your Notes
Homework
Google Classroom
Quiz