1) ( 2x + 1 ) ( x + 4 )
2) ( 2x + 3 ) ( 5x - 4 )
3) ( 3x - 2 ) ( 2a - 1 )
4) ( 5a - 3b ) ( 4a - b)
5) ( 2m + 3n ) ( 2m - 5n )
6) ( 3x + 2y ) ( x - y )
7) ( 5b - 4c ) ( 2b -2c )
8) ( p - 3q ) ( 8p + 5q )

1) (2Х+1)(Х+4)=2х²+8х+х+4=2х²+9х+42) (2х+3)(5х-4)=10х²-8х+²5х-12=10х²-3х-123)(3х-2)(5х-4)=15х²-12х-10х+8=15х²-22х+84)(5а-3в)(4а-в)=20а²-5ав-12ав+3в²=20а²-17ав+3в²5)(2т+3п)(2т-5п)=4т²-10тп+6тп-15п²=4т²-4тп-15п²6)(3х+2у)(х-у)=3х²-3ху+2ух-2у²=3х²-ху-2у²7)(5в-4с)(2в-2с)=10в²-10св-8св+8с²=10в²-18св+8с²=5в²-9св+4с²8)(р-3q)(8p+5q)=8p²+5pq-24pq+25q²=8p²-19pq+25q²