You can use integer counters to model 2
–
–
1
.Start with 2 negative counters.
Then take away 1 positive counter. You'll need to first add zero pairs until you have 1 positive counter to take away.
Subtract.
–
–
1
=
ref_doc_title.
Jumping to level 1 of 1
Excellent!
Now entering the Challenge Zone—are you ready?


