Respuesta :
Answer:
Answer 21ab
Step-by-step explanation:
First you do 3 times 3a which you get 9a then to 3 times 4b and you get 12b. So 12b plus 9a equals 21ab
Answer:
9a+12b
Step-by-step explanation:
use the distributive property
since the three is on the outside of the parethesis distribute it
3x3a= 9a
then do the same with 4b
3x4b= 12b
final answer
9a+12b