Hello! Your answer would be -10 degrees.
The temperature starts out eight degrees below zero. 0 - 8 = -8. Therefore, it starts off at -8 degrees.
Then, it increases by 5 degrees. Therefore, add 5 to -8. -8 + 5 = -3. Therefore, the next day has a temperature of -3 degrees.
Finally, it decreases by 7 degrees. -3 - 7 = -10. This shows us our final result - -10 degrees.
Hope this helps!