LetX1={5,10,15,20}andY1={5,10,15,20 ,25}. Using the formal definition of a func-tion, determine which of the following subsets ofX1×Y1correspond to the functions ofX1→Y1.
Justifyyour answer by providing reasons why each is or is not a function.
a) 1(a)f={(5,20),(10,15),(5,10),(15,5) ,(20,5)}
b) 1(b)f={(5,25),(10,5),(15,5),(20,10) ,(5,25)}
c) 1(c)f={(5,5),(10,5),(15,5)}

Option b) is the answer

Step-by-step explanation:

A function from X₁ to Y₁ is an object f such that every x in X₁ is uniquely associated with an object f(x) = y in Y₁.

Then

1(b)f={(5,25),(10,5),(15,5),(20,10),(5,25)} is the correct answer.

It follows that

f(5) = 25

f(10) = 5

f(15) = 5

f(20) = 10

the sum of the lengths of any two sides of a triangle is greater than the length of the third side. if you take the three sides of a triangle and add them in pairs, the sum is greater than (not equal to) the third side. if that is not true, then it is not possible to construct a triangle with the given side lengths.

step-by-step explanation:

$650 per month plus utilities

step-by-step explanation:

just based on the info you gave, it would seem more cost effective to rent at $650 per month plus utilities.   if utilities are, in fact, $150 per month, your monthly living costs would be $800 as opposed to the other option of $825.