The outside temperature when Kimberly entered the theater was $-8^\circ F$, and it decreased by $6^\circ F$ while she was inside.

To find the temperature when she left, subtract $6^\circ F$ from $-8^\circ F$:

$-8^\circ F - 6^\circ F = -14^\circ F$

Thus, the temperature when Kimberly left the theater was $-14^\circ F$.

Would you like more details or have any questions?

Here are some related questions:

1. If the temperature had decreased by 10°F instead of 6°F, what would the new temperature be?
2. What would the temperature be if it had increased by 6°F instead of decreasing?
3. How much would the temperature need to change for it to reach 0°F from –8°F?
4. What would the temperature be if it dropped 4°F more after reaching –14°F?
5. If the temperature had started at 5°F and dropped by 6°F, what would it be?

Tip: When dealing with negative temperatures, think of subtraction as moving further down the number line.