Question

Which equations show that the set of whole numbers is not closed under subtraction?

Choose all answers that are correct.

A.
1 – (–2) = 3

B.
1 – 2 = –1

C.
2 – 0 = 2

D.
2 – 4 = –2

Answer 1

First, we need to know what whole numbers are. Can you give me an example of numbers that are not whole numbers?

Answer 2

Ah, you're not here. Well, whole numbers are the numbers that look like 0, 1, 2, 3, 4, ...

If we add any two whole numbers, we get another whole number.
Take 2 and 99 for example. 2 + 99 is 101, and 101 is a whole number. The idea that we can add any two whole numbers and guarantee that you get a whole number is called the "closure property of addition." It is similar to the idea that if you mate two cats, you will get a baby cat.

However, this doesn't work for subtraction. If we take 95-100, we get -5, which is not a whole number (because it's negative). We mated two cats, but they gave birth to a puppy instead.

Answer 3

back sorry

Answer 4

closing question