Hi there! :)
Answer:
b=19
*The answer must have a positive sign.*
Explanation:
Lesson: Addition/Subtraction/Multiplication/ and Division property of equality
First, you add by 7 from both sides of an equation.

Then, you add by the numbers from left to right.

Final answer is b=19
I hope this helps you!
Have a nice day! :)
:D
-Charlie
Thank you so much! :)