1. Warm up 1.(12x 2 + 8x – 6) – (9x 2 – 2x + 5) 2.Find the area 3.(x – 5)(-3x 2 + 6x – 8) x + 4 2x – 1

2. Questions over hw?

3. 2/8/2016 Day 26 & 27 GSE Algebra I Today’s Question: What does the acronym GCF mean, how do we find it and how do we use it to factor a polynomial? Standard: MM1A1f- Factor expressions by GCF, grouping, trial and error, and special products.

4. GCF What does it stand for? What is it?

5. What is the greatest common factor?? 24 36 1, 2, 3, 4, 6, 9, 12, 18, 36 1, 2, 3, 4, 6, 8, 12, 24

6. What is the greatest common factor?? 5a 35 1, 5 a 1, 5, 7

7. What is the greatest common factor?? 3y -8xy 1, 3 y 1, 2, 4, 8 x y

8. What is the greatest common factor?? 22x 2 -11x 1, 2, 11, 22 x  x -1, 11 x

9. What is the greatest common factor?? -4x 6 -x 4 -2x 2 -x 2 -1, 2, 4 x  x  x  x  x  x -1 x  x  x  x -1, 2 x  x

10. What is the greatest common factor?? 8x 3 y 5 -20x 5 y 3 12x 7 y 6 4x 3 y 3 1, 2, 4, 8 x  x  x y  y  y  y  y -1, 2, 4, 5, 10, 20 x  x  x  x  x y  y  y 1, 2, 3, 4, 6, 12 x  x  x  x  x  x  x y  y  y  y  y  y

11. What is the greatest common factor?? x52yx52y PRIME xxxxxxxxxx 1, 2 y

12. Factoring means to write as a product Always look for a Greatest Common Factor 1 st. Factor 4x + 6y What is their greatest common factor? = 2( ) 2x + 3y Now, DIVIDE each term by the GCF.

13. 8a 3 + 4a 2 + 12a Factor What is their GCF? = 4a( ) 2a 2 + a 40x 2 – 100xy – 80y 2 = 20( ) 2x 2 – 5xy Now, DIVIDE each term by the GCF. + 3 – 4y 2

14. 2h 2 k + 2k Factor What is their GCF? = 2k( ) h2h2 + 1 12x 5 y 2 + 9x 4 y 2 - 6x 3 y 2 = 3x 3 y 2 ( ) 4x 2 + 3x Now, DIVIDE each term by the GCF. – 2

15. CW/HW GCF Practice