# FORMULA FOR A SQUARE MINUS B SQUARE

a- b2 = (a + b)(a - b)

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Problem 1 :

x2 - 16

Solution :

(x² - 16) can be written as x² - 4²

Here a = x, b = 4

a² - b² = (a + b) (a - b)

x² - 4² = (x + 4) (x - 4)

Problem 2 :

y² - 49

Solution :

(y² - 49) can be written as y² - 7²

Here a = y, b = 7

y² - 7² = (y + 7) (y - 7)

Problem 3 :

x² - 25

Solution :

(x² - 25) can be written as x² - 5²

Here a = x, b = 5

x² - 5² = (x + 5) (x - 5)

Problem 4 :

4x² - 25

Solution :

(4x² - 25) can be written as (2x)² - 5²

Here a = 2x and b = 5

(2x)² - 5² = (2x + 5) (2x - 5)

Problem 5 :

16 - y²

Solution :

(16 - y²) can be written as 4² - y²

Here a = 4 and b = y

4² - y² = (4 + y) (4 - y)

Problem 6 :

m² - 36

Solution:

(m² - 36) can be written as m² - 6²

Here a = m, b = 6

m² - 6² = (m + 6) (m - 6)

Problem 7 :

4m² - 49

Solution :

(4m² - 49) can be written as (2m)² - 7²

Here a = 2m and b = 7

(2m)² - 7² = (2m + 7) (2m - 7)

Problem 8 :

9m² - 16

Solution:

(4m² - 49) can be written as (3m)² - 4²

Here a = 3m and b = 4

(3m)² - 4² = (3m + 4) (3m - 4)

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