Answer:
12.) x=3
13.) x=4
EXPLANATION:
in question 12 you divied 18 by 6x and you get 3
in question 13 since the 2 is already by it's self you add the ten to the negeative ten and cancel that out then add the ten to the 2 and you get 3x=12 and the last step for that is you divide 12 by 3 and you get 4
i hope this helped you!!