1. Class Greeting

2. Chapter 6 – Factoring Lesson 6-3c Factoring Trinomials ax2 + bx + c
by Grouping

3. Objective: The student will learn how to factor the by Grouping.

4. Factor by grouping.
a = 15 and c = –8 therefore ac = –120
What 2 numbers multiply to make -120 and add to make –14?
6 and –20
Replace -14b with 6b – 20b
Group
15b2 + 6b – 20b – 8
(15b2 + 6b) – 1(20b + 8)
3b(5b + 2) – 4(5b + 2) 6b
–20b
–14b TRUE
Answer:

5. Factor by grouping.
4x2 + 27x – 40
a = 4 and c = –40 therefore ac = –160
What 2 numbers multiply to make -160 and add to make 27?
32 and –5
Replace 27x with 32x – 5x
4x2 + 32x –5x – 40
Group
(4x2 + 32x) + (–5x – 40)
4x(x + 8) – 5(x + 8)
(4x – 5)(x + 8)
-5x
32x
27x TRUE
Answer:
(4x – 5)(x + 8)

6. Lesson Summary:
Objective: The student will learn how to factor the by Grouping.

7. Preview of the next Lesson:
Objective: The student will do a
6-1 to 6-3 practice test.

8. Kahoot!

9. Stand Up Please

10. Review: 6.3b Mini-Quiz 1. Factor 2x2 + 8x – 42
3. Factor 3x3 + 4x2 + 2x
4. Factor 9x2 – 24x + 15