Question

factorise: 25 - a2 - b2 - 2ab​

Answer 1

Step-by-step explanation:

$25 - a ^{2} - b ^{2} - 2ab \\ 5 ^{2} - a ^{2} - b ^{2} - 2ab \\ 5 ^{2} - (a ^{2} + b ^{2} + 2ab) \\ 5 ^{2} - (a ^{2} + b ^{2} + 2 \times a \times b) \\ 5 ^{2} - (a ^{2} + b ^{2} ) \\ (5 + a - b )(5 - a + b )$

Answer 2

Answer:

( 5 + a + b ) ( 5 - a - b )

Step-by-step explanation:

25 - a² - b² -2ab

= 25 - ( a² + b² + 2ab )

= 5² - ( a + b )²

= ( 5 + a + b ) [ 5 - ( a + b )]

= ( 5 + a + b ) ( 5 - a - b )