Answer:
Simplifying
12b + -1b = 77
Combine like terms: 12b + -1b = 11b
11b = 77
Solving
11b = 77
Solving for variable 'b'.
Move all terms containing b to the left, all other terms to the right.
Divide each side by '11'.
b = 7
Simplifying
b = 7
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