#### Answer

$(-17)^{-8}$ is positive because when the negative exponent rule is applied, the denominator's power is even (which is $8$). Any non-zero real number raised to an even power is positive.
Refer to the step-by-step part below for a detailed explanation.

#### Work Step by Step

RECALL:
For any nonzero real number $a$, $a^m$ is positive when $m$ is an even integer.
The reason for this is that an even power $m$ means there are $\frac{m}{2}$ pairs of identical factors.
Since the product of two numbers with the same sign is positive, then having $\frac{m}{2}$ pairs of identical factors means that the product will surely be positive.
Note that $a^{-m} = \dfrac{1}{a^m}, m \ne 0$.
Applying this to $(-17)^{-8}$ gives $\dfrac{1}{(-17)^8}$.
Since the denominator involves an even power of $-17$, then the denominator is positive.
Thus, the quotient will also be positive as the quotient of two positive numbers is positive.