<h3>
Answer: 0</h3>
=================================================
Explanation:
Think of z as having 1 zebra
2z means we have 2 zebras
If we started with 2z, and subtracted off 2z, then we're left with 0 zebras. We write this as 0z or just 0 since 0 times anything is 0.
---------
As another example:
Let's say we wanted to simplify 5z - 2z
Well that's the same as saying "5 zebras take away 2 zebras". We'd be left with 3 zebras because 5-2 = 3
Since 5-2 = 3, this leads to 5z-2z = 3z. The difference is that I tacked 'z's onto each number.
