Question

25(m+n)² - 9 ( m - n)² factorise​

Answer 1

Answer:

Step-by-step explanation:

25 x² + 25 y² + 50 xy - 9 x² - 9 y² + 18 x y

= 16 x² + 16 y² + 68 x y  

= 4 (4 x² + 17 x y + 4 y²)

= 4 ( 4x + y) (x + 4 y)

Another way:  

 we use a² - b² = (a+b) (a-b)

 

so  25 (x+y)²  - 9 (x-y)²

=  [ 5(x+y)  + 3 (x-y) ] * [ 5 (x+y)  - 3 (x-y) ]

=  [ 8 x + 2 y ] * [ 2 x + 8 y]

= 4 * (4x + y) (x + 4y)

Answer 2

Answer:

no answer fing this question