Question

Which equations support the fact that rational numbers are closed under subtraction?

Select each correct answer.




4.5−0.5=4

2√3−√3=√3

√8−√8=0

5√4−√4=4√4

Please help!

Answer 1

I don't know, that's the question I was asked and that's why I need help.

Answer 2

I don't know what a snap pic is

Answer 3

If you take any two rational numbers, subtract them, and get a rational number as a result, then this means the set of rational number is closed under subtraction.

In other words,
let A and B be rational numbers
C = A-B is also rational if rational numbers was closed under subtraction

Answer 4

For choice A we have
4.5 = 9/2 which is rational
0.5 = 1/2 also rational

4.5−0.5=4 which is rational because 4 = 4/1
So this is one example where subtracting two rational numbers leads to some other rational number. It shows closure.

There's one other answer.

Answer 5

What is it?

Answer 6

Note how \(\sqrt{4} = 2 = \frac{2}{1}\) which shows it's rational
This means \(5\sqrt{4}\) and \(4\sqrt{4}\) are also rational. This is sufficient to show that D is the other answer that shows an example of closure under subtraction.

Answer 7

Another way to phrase closure is to say (rational) - (rational) = rational

Answer 8

Ohhh, okay. Thank you!

Answer 9

No problem