Question

Como resolver a inequação 5 - (2x + 7) < - x + 3 . (-x + 4)?

Answer 1

 5 - (2x + 7) < - x + 3 . (-x + 4)

5 - 2x -7 < -x -3x + 12

-2x -2 < -4x + 12

-2x + 4x < 12 +2

2x < 14

x < 7

Answer 2

Olá, Danilo.

 

$<var> 5 - (2x + 7) < - x + 3 . (-x + 4) \Rightarrow\\\\ 5-2x-7 < -x-3x+12 \Rightarrow\\\\ -2x+x+3x<12-5+7 \Rightarrow\\\\ 2x<14\Rightarrow\\\\ x<7\\\\ \therefore \boxed{S=\{x\in\mathBB{R}|x<7\}}</var>$