The term "closed" in math means that if you take two items from a set, do some operation, then you'll always get another value in the same set (sometimes you may get the same value as used before). For example, adding two whole numbers leads to another whole number. We therefore say "the set of whole numbers is closed under addition". This applies to integers as well because integers are positive and negative whole numbers. So we can say that integers are closed under addition.
Integers are not closed under division. Take two integers like 2 an 5 and divide: 2/5 = 0.4 which is not an integer. Integers don't have decimal parts.
The set of whole numbers is {0,1,2,3,...} and we can subtract the two values 1 and 2 to get 1-2 = -1. The order matters here. Subtracting a larger value from a smaller leads to a negative. The value -1 is not in the set of whole numbers. So we can say that whole numbers is not closed under subtraction
Finally, the set of irrational numbers is closed under addition. Adding any two irrational numbers leads to another irrational number. For instance, pi+sqrt(2) = 3.142 + 1.414 = 4.556; I'm using rounded decimals as approximate values. An irrational number is one where we cannot write it as a fraction of integers. Contrast that with a rational number in which we can write it as a fraction of integers. Example: 10 = 10/1 is a rational number.
Answer:
7^2 + 5^2 = 49 + 25 = 74
hypotenuse = square root of 74
Answer is B
Step-by-step explanation:
So set both equations equal to each other then solve out of x and plug it back into the x equation to find the angles so start with x+5=2x+10 then subtract x from 2x and you will have 1x then subtract 10 from 5 leaving you with negative 5 then x equals negative 5 and then plug it back into the equation so for example 2 times negative 5 equals negative 10 plus positive 10 equals 0 so therefore x equals 0
Answer: 5 pounds of ground beef ( don't see second :-( )
Step-by-step explanation: I found the unit rate per pound ( 2.25 ) and then multiplied that by the other pounds to compare the two prices and I only found 5 pounds to be incorrect, but I'll keep digging, hope this helps!
