Question

Zad. 12.7:A,B,C,D
Zad. 12.9:A,B,C,D

Answer 1

12.9
a
x-5+1<5 V x-5+1>-5
x<9 V X>-1


X∈(-1;9)

b

x+6+1>4 V x+6+1<-4

x>-3 V x<-11

x∈ (-∞;-11)V(-3;∞)

c

4-x-2>3 V 4-x-2<-3
X<-1 V X>5

X∈(-∞;-1) V (5;∞)

d

2-x+9>7/3 V 2-x+9<-7/3
x<8²/₃ V X> 13⅓

X∈ (-∞; 8²/₃ ) V (13⅓;∞)

12,7

a
x-7=9 V x-7=-9
x=16 V x=-2

b

x+9=1 V x+9=-1
x=-8 V x=-10

c

x-8=1 V x-8=-1
x=9 V x=7


d
x+7=0
x=-7