You first need to multiply -3 and -8b. That will be 24b. Then you multiply -3 times 7. That will be -21. On the other side, you will multiply 3 times 2b which will equal 6b. Then you multiply 3 by -1. You will get -3. So at this point, the equation should look like this, 24b-21=6b-3. Then add 21 to both sides. You will have this equation, 24b=6b+18. Then subtract 6b from both sides, 18b=18. Finally, divide 18 from both sides to get your final answer of b=1.