Answer:
w=9
Explanation:
A negative exponent means that you take the reciprocal of the positive exponent.
For example, take 2^-2:
2^2 = 4. By the rule above,
2^-2 = 1/4.
According to a calculator, that's right.
Let's now take your question.
b^(-w) = 1/(b^9)
Because of the rule we just established, we know that
b^w = b^9 (taking the reciprocal, making the left-side exponent positive)
Since, if the bases are equal, the exponents are equal, the answer is:
w = 9