GCF Basics
DOTS Basics
Factor using the GCF
True or False
Factoring the difference of two perfect squares
100

6x + 12

6(x + 2)

100

x² − 9

(x − 3)(x + 3)

100

3x2-12x

3x(x-4)

100

The GCF of 8x and 12x is 4x.

TRUE

Both terms are divisible by 4x.

100

16x² − 1

(4x − 1)(4x + 1)

200

8x + 20

4(2x + 5)

200

x² − 25

(x − 5)(x + 5)

200

3x+6

3(x+2)

200

x² − 36 = (x − 6)(x + 6).


TRUE

This is a difference of two squares.

200

9-x2

(3+x)(3-x)

300

12x² + 18x

6x(2x + 3)

300

4x² − 49

(2x − 7)(2x + 7)

300

4ab-8

4(ab-2)

300

12x² + 18x = 6x(2x + 3).


TRUE

300

25y2-4

(5y+2)(5y-2)

400

15a²b + 25ab²

5ab(3a + 5b)  

400

9a² − 64

(3a − 8)(3a + 8)

400

4ab2-12a2b

4ab(b-3a)

400

9x² − 16 = (3x − 4)².

FALSE

The correct factorization is (3x − 4)(3x + 4).

400

4x2-400

(2x + 20) (2x - 20)

500

24x³y² − 36x²y³

12x²y²(2x − 3y)

500

25x⁴ − 81y²

(5x² − 9y)(5x² + 9y)

500

3x2y2-2xy

xy(3xy-2)

500

The expression x² − 25 can be factored as (x − 5)(x + 5).



TRUE!

This is a difference of two squares.

500

x2+100

Can not be factored because of the plus sign.