The answer you are looking for is b = -6.
There are 2 ways to find this. You could use...
- Add together 7 and 12 to get 19, then subtract 19 from both sides to get b = -6. OR...
- Subtract 12 from both sides to get b + 7 = 1, then subtract 7 from both sides to get b = -6.
Either way, you will get the same answer of b = -6. One method is just longer than the other. I hope this helps!