Solving Equations with Brackets

Question 1:

5x+7=70
x =7

Question 2:

3x+7=39
x =6

Question 3:

33x8=21
x =5

Question 4:

8x+5=80
x =5

Question 5:

9x7=-9
x =6

Question 6:

12x3=108
x =12