Respuesta :

Answer:

1. x>18    2.x<-18     3. x>21     4. x>-7     5. x<2     6. x>-2     7. x<12    8.x<-6

Step-by-step explanation:

1. x/2>9 Pretend the inequality is an equal sign...

x/2=9 *2            x=18

If x>18; 20>18

20/2 = 10

10>9 so it works

If x<18      10<18

10/2 = 5

5<9 so it dosent

2. x/-2>9

x/-2=9

x=-18

If x>-18

0>-18

0/-2=0

0<9 so it doesent work.

x<-18; x=-20

-20/-2=10

10>9 So it works

3. x-7>14 --> x-7=14 ---> x=21

If x>21; x=22 --> 22-7=15; 15>14 (it works)

If x<21; x=20 --> 20-7=13; 13<14 (so it does not work)

4. x-7>-14 --> x-7=-14 --> x=-7

If x>-7; x=0 ---> 0-7=-7 --> -7>14 (so it works)

If x<-7; x=-10 ---> -10-7=-17 --> -17<14 (so it does not work)

5. 5x<10 --> 5x=10 --> x=2

If x>2 x=3 --> 5*3=15 15>10 (does not)

If x<2 x=1 --> 5*1=5 5<10 (works)

6. -5x<10 -5x=10  x=-2

If x<-2 x=-3 -3*5=-15 -15<10 (no)

If x>-2 x=0 5*0=0 0<10 (works)

7. x-3<9  x-3=9 x=12

if x>12 x=13 13-3=10 10>9

If x<12 x=10 10-3=7 7<9 (works)

8. x-3<-9 x-3=-9   x=-6

if x>-6; x=13; 13-3=10 10>-9

if x<-6 x=-10 -10-3=-13   -13<-9 (works)