math problem help!?

Question

ok go to this link, and do the math problem. I couldn't write it out on here because I didn't know how to write out those sidways U things. thanks

http://i8.photobucket.com/albums/a13/Drgnbllgt121/DSC00656.jpg

Answer 1

It often helps to think of the subset symbol as like a "C" meaning "is contained in".

Integers are numbers like ... -4, -3, -2, -1, 0, 1, 2, 3, 4, ...; they're whole numbers and their opposites.
Rational numbers are basically anything that can be written as a fraction.

Since you can write every integer as a fraction (for instance, 2 is the same as 6/3), the integers are contained in the rational numbers. So the integers are a subset of the rational numbers.

However, not every rational number is an integer (for instance 1/2 and -2/3 aren't). So the rational numbers aren't contained in the integers. The rational numbers AREN'T a subset of the integers.

Answer 2

the first one is true, the second on is false. all integers are rational numbers. all rational numbers are NOT integers, for example, 1/2 is rational, but not an integer. the sideways u, "is a subset of" just means that it belongs to that group. So, to say integers are a subset of rational numbers, it means that all integers also fall into the category of rational numbers.