Methods used in our classroom.

2.  Factor out the largest monomial in
common
3x + 9 2x2 – 4x + 8
3(x + 3) 2(x2 – 2x + 4)

3.  Look for a subraction sign
 Look for squares on each side
W2 - 16
(w + 4)(w – 4)
4x4 – 36
(2x2 + 6)(2x2 – 6)

4.  Usually written ( + )2 or ( - )2
 Remember this means ( + ) ( + ) or ( - )( - )
 Square the first term
(2x + 3)2 => 4x2
 Multiply and double the terms
(2x + 3)2 => 4x2 + 12x
 Square the second term
(2x + 3)2 => 4x2 + 12x + 9
 Trinomial answer is the result

5.  EASY because the first term has coefficient of 1
Ex. x2 + 4x + 3
Ex. y2 – 5y – 6
 Find the factors of the last constant term that can
add to create the second linear term
› Multiply to make 3, add to make 4 => 1, 3
› Multiply to make -6 and add to make -5 => -6, 1
Ex. x2 + 4x + 3 Ex. y2 – 5y – 6
(x + 1)(x + 3) (y – 6)(y + 1)

6. 2x2 – 5x – 3
Arc method – multiply the first and last coefficients
together above the problem
-6
2x2 – 5x – 3
Find numbers that multiply to make the arc and add to
make the middle term
1, -6
Replace the middle term with these numbers
2x2 +1x – 6x – 3
Circle the first two and last two
Factor out GMF of each circle
x(2x + 1) – 3(2x + 1)
Remaining () should be the SAME!
(2x + 1)(x – 3)