Question

Упростите выражение:

2
A) (x-4)-(x+1)(x+2)

2
Б) 5(a+b)- 10ab

Answer 1

$\displaystyle \tt (x-4)-(x+1)(x+2)=x-4-(x^2+2x+x+2)=x-4-(x^2+3x+2)=\\\\ \displaystyle \tt =x-4-x^2-3x-2=-2x-6-x^2=\bold{-x^2-2x-6}$

$\displaystyle \tt 5(a+b)-10ab=\bold{5a+5b-10ab}$