Rational numbers, whole numbers, negative numbers, even numbers, integers
You could make a case for any of them.
The numbers which divide 2 and 9 are indirectly divisible by 18.
The prime numbers (factors) of 18 are: 2 and 3
There are two pairs of prime numbers that express 18 as the sum of two prime numbers: 7 + 11 = 18 and 5 + 13 = 18.
6 and 18
The set of even numbers
To any set that contains it! It belongs to {18}, or {sqrt(2), 18, pi, -3/7}, or {18, bananas, France, cold} or all whole numbers between 3 and 53, or multiples of 2, or composite numbers, or counting numbers, or integers, or rational numbers, or real numbers, or complex numbers, etc.
Integers (whole numbers, without a decimal point, including negative whole numbers) are real numbers; they are rational; therefore they are not irrational.
You could make a case for any of them.
18
26 because all of the other numbers are added from 2. for example, 14+2=16, and 16+2=18
The question is equivalent to asking if there are two numbers whose sum is 6 (the coefficient of x) and whose product is 18 (the constant term). Since there are no such real numbers, the answer is NO. There is a solution in the complex domain but the normal context for such questions is the real numbers.
group 18
1,2,3,6,9 & 18 !
18 and 6.
5 and 41 are prime numbers but 18 is a composite number
Group 18.