please tolong bantu aku

[tex](6x - y)(2y - 5x) \\ 12xy - 30 {x}^{2} - 2 {y}^{2} - 5xy \\ - 30 {x}^{2} + 12xy - 5xy - 2 {y}^{2} \\ - 30 {x}^{2} + 7xy - 2 {y}^{2} [/tex]

( 6x - y ) . ( 2y - 5x )
( 12xy - 30x² ) . ( 2y² - 5xy )
= -30x² + 7xy - 2y² (b.)

(semoga membantu, mohon maaf kalau salah)