Answer: B = 1
Explanation:
You want to get b alone, first, you will subtract 3.6. What you do on one side you do to the other
3(1.2b - 1) + 3.6 = 4.2
3(1.2b - 1) + 3.6 - 3.6 = 4.2 - 3.6
Since the 3 is multiplied, we will do the opposite to eliminate it, Divison. So divide each side by 3.
3(1.2b - 1) = 0.6
3(1.2b - 1)/3 = 0.6/3
Then we will add one to each side.
1.2b - 1 = 0.2
1.2b - 1 + 1 = 0.2 + 1
The last step is to divide each side by 1.2 to find b.
1.2b = 1.2
1.2b/1.2 = 1.2/1.2
b = 1