Question

Factorise 25x cube y - 81 xy​

Answer 1

Answer:

xy( 25x ^2 - 81 )

Step-by-step explanation:

see the attachment.

Answer 2

Answer:

$25x {y}^{3} - 81xy \\ xy(25 {y}^{2} - 81) \\ xy( {5}^{2} {y}^{2} - {9}^{2} ) \\ xy(( {5y)}^{2} - {9}^{2} ) \\ xy(5y - 9)(5y + 9)$