Respuesta :

Answer:

Step-by-step explanation:

3x-9<12

You carry the 9 to the other side and do the inverse(opposite of take away

3x<12+9

3x<21

3x/3x

To cancel out the the x you must devide them together and then devide 21÷3

21/3=7

X<7

Answer: x<7 or (-infinity,7)

Step-by-step explanation:

3x-9<12

3x<21

x<7