Final answer:
The equation A-9x-7 is a linear equation.
Step-by-step explanation:
The equation A-9x-7 is a linear equation since it represents a linear relationship between variables.
In this case, the variable x is multiplied by a constant -9, and then it is subtracted by a constant 7.
The equation does not involve any exponents or other non-linear operations.
Therefore, the correct answer is A-9x-7.