Question

a) (x + 2)(x – 5) -3x(1 - 2x), б) (а + 3)(а - 2) + (a - 3)(a + 6), в) (x - 7)(3x - 2) – (5x + 1)(2x – 4).​

Answer 1

Объяснение:

а)

(х+2)(х-5)-3х(1-2х)=х²-5х+2х-10-3х+6х²=

=7х²-6х-10

б)

(а+3)(а-2)+(а-3)(а+6)=

=а²-2а+3а-6+а²+6а-3а-18=

=2а²+4а-24

в)

(х-7)(3х-2)-(5х+1)(2х-4)=

=3х²-2х-21х+14-(10х²-20х+2х-4)=

=3х²-2х-21х+14-10х²+20х-2х+4=

= -7х²-5х+18