What is -9 - 8?

For -9 - 8, we start at -9 on the number line and move an additional 8 units in the negative direction. Since -9 is already negative, adding -8 means increasing the negative total. Moving from -9 by another 8 units results in -17. This is because combining two negative values leads to a more negative outcome, which is consistent with the properties of integer addition. Thus, the calculation of -9 - 8 results in a sum of -17 due to this cumulative leftward shift.