Which sets are not closed under subtraction

If you're referring to the different sets of real numbers, it's the ones that you could try to do subtraction and not get an answer that still in that set.

For example, natural numbers (aka 1, 2, 3, 4, ...) are not, because 7 - 11 = -4 and -4 is not a natural number.

Also, whole numbers (aka 0, 1, 2, 3, 4, ...) has the same issue.

Basically any set of real numbers that doesn't include negative numbers will have this issue.

93.8

step-by-step explanation:

lets say, first number = x

second number = 3x+7

total = 49

(x)+(3x+7)= 49

4x+7 = 49

4x = 42

x = 42/4

x= 10.5

x= 10.5

3x+7 = 3(10.5)+7 = 93.8

hope this

76%

step-by-step explanation:

24% are dogs and the remaining is 76% because 100-24=76