Factor a Difference of Squares

3x² - 75

• 3( x + 5 ) ( x - 5 ) 

• Prime

• ( x + 5 ) ( x - 5 ) 

• 3( x - 5 ) ( x - 5 ) 

r² - 9t²

• (r + 3t) (r - 3t)

• (r - 3t) (r - 3t)

• (3r + t) (3r - t)

• Can't factor using Diff. of Squares

Which one is false about the difference of two squares?

• We can factor because there is addition sign.

• We can factor because there is a perfect squared number (Example: x², 25, 49)

• Formula: a² - b² = (a + b) (a - b)

• We can factor because there is minus sign.

x² - 9

• (x + 3)²

• (x + 3) (x - 3)

• (x - 3)²

• x + 3(x - 3)

x² - 16

• (x + 4) (x - 4)

• (x + 8) (x - 2)

• (x + 4)²

• x + 4(x - 4)

25x² - 36y²

• 5x + 6y(5x - 6y)

• (5x + 6y) (5x - 6y)

• (5x + 6y)²

• (5x - 6y)²

64x² - 81y²

• (8x + 7y) (8x - 7y)

• (8x + 9y) (8x - 9y)

• (6x + 7y) (6x - 7y)

• (6x + 9y) (6x - 9y)

49x² - 144y²

• (7x + 16y) (7x - 16y)

• (7x + 12y)²

• (12x + 7y) (12x - 7y)

• (7x + 12y) (7x - 12y)

x⁴ - 100y²

• (x² + 10y) (x² - 10y)

• (x + 10y) (x - 10y)

• (x + 10y) (x³ - 10y)

• (x³ + 10y) (x - 10y)

4x² - 16

• 4(2x + 4) (x - 2)

• 4(4x + 2) (x - 2)

• (2x + 4) (2x - 4)

• 4(x + 2) (x - 2)