Add -20 and -17

-20 + -17 = -37

Add -33 and 40

-33 + 40 = 7

To add -20 and -17, follow these steps:

1. Start with the given numbers: -20 and -17.
2. Add the two numbers together:
-20 + (-17) = -20 - 17 = -37

Therefore, the sum of -20 and -17 is -37.