Question

Can someone please help
calculate the given expressions
199 - 199
-67 - -67
21 + -21
do i add and subtract normally

Answer 1

199-199=0
-67 - -67= 0
21 + -21= 0

I'm thinking that's how it goes.

Answer 2

yep, subtracting a negative is like adding. and the others are normal, adding a negative is like subtracting.