Factoring ContinuedFactoring Continued“Down Under”“Down Under”

Used to factor trinomials Used to factor trinomials when a does not equal 1when a does not equal 1

ExampleExample

3 10 82y y Because of the 3, we use the down under method.

Setup:

3

Players: Factors of a times c

3 x 8 = 24

So we follow the same rules w/ + +

Factors of 24 that + to 10

6 4(3y ) (3y )+ +

# “down under” should be able to be divided into one of the binomials on top. MUST GO INTO BOTH!!!

(y + 2)(3y + 4)

ExampleExample

2 9 102t t

(2t )(2t )

2

+ +5 4

(2t + 5)(t + 2)

Your turn:Your turn:

Factor:Factor:

3 13 42x x

(x + 4)(3x + 1)

2 9 72a a

(a – 1)(2a – 7)

14 36 2 2t t 2 14 362t t (2t + 18)(2t - 4)

2

2(t + 9)(t -2)

ExampleExample

276 2 tt 3108 2 mm

6

#6#6 tt

6

3646 tt

32

3646

tt

1223 tt

8

#8#8 mm

42

4868

mm

1234 mm

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