To solve this, we will follow the reflection steps carefully.

Step 1: Reflect point $D(-3, -6)$ over the x-axis

When reflecting a point over the x-axis, we change the sign of the $y$-coordinate, while the $x$-coordinate remains unchanged. So:

$D'(-3, -6) \rightarrow (-3, 6)$

Now, point $D'$ is at $(-3, 6)$.

Step 2: Reflect point $D'(-3, 6)$ over the y-axis

When reflecting a point over the y-axis, we change the sign of the $x$-coordinate, while the $y$-coordinate remains unchanged. So:

$D'(-3, 6) \rightarrow (3, 6)$

Thus, the coordinates of $D''$ (point $D$ reflected over both axes) are $(3, 6)$.

Final Answer:

The ordered pair that describes the location of $D''$ is $(3, 6)$.

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Would you like further clarification on any step? Here are 5 related questions to expand your understanding:

1. How do you reflect a point over the y-axis?
2. What happens if you reflect a point over both axes simultaneously?
3. How do you reflect a point over the origin?
4. What are the general rules for reflections in the coordinate plane?
5. Can a point's location remain the same after a reflection?

Tip: Reflections in the coordinate plane follow simple rules: over the x-axis, you negate the $y$-coordinate, and over the y-axis, you negate the $x$-coordinate.