Answer:
2b - 15
Step-by-step explanation:
b - 7 + b - 8
You combined the two b's correctly, but didn't combine the two constants, -7 and -8.
Those combine to -7 + (-8) = -7 - 8 = -15, so the final answer is
2b - 15
you have -7 and are subtracting 8 more, so you are moving 8 units left on the number line, so it has to get more negative.
