Question

Factorise= 9 - x² + 4xy - 4y²​

Answer 1

Answer:

( 3 + x - 2y ) ( 3 - x - 2y )

Step-by-step explanation:

x² + 4xy - 4y²​

= x² + 2 ( x ) ( 2y ) - 4y²​

= ( x - 2y )²​

9 - x² + 4xy - 4y²​

= 3²​ - ( x - 2y )²​

Formula : -

a² - b² = ( a + b ) ( a - b )

Here,

a = 3

b = x - 2y

3²​ - ( x - 2y )²​ = ( 3 + x - 2y ) ( 3 - x - 2y )