SOLUTION: Is the following relation a function? (1, 2), (3, 4), (5, 5)?

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Question 470900: Is the following relation a function? (1, 2), (3, 4), (5, 5)?
Found 2 solutions by nerdybill, MathLover1:
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
Yes, because for each value of 'x', there is a unique value of 'y'.
("vertical line test")

Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

Is the following relation a function? (1, 2), (3, 4), (5, 5)

recall: A relation is just a set of ordered+pairs.
There is absolutely nothing special at all about the numbers that are in a relation. In other words, any+bunch of numbers is a relation so long as these numbers come in pairs.
The domain and range of a relation:
The domain is the set of all the first numbers of the ordered pairs . In other words, the domain is all of the x-values.

The range is the set of the second numbers in each pair, or the y-values.


In the relation above the domain is { 1, 3, 5 }
And the range is { 2, 4, 5 }

What} makes a relation a function ?
Functionsare a special kind of relation .
At first glance, a function looks just like a relation. It's a set of ordered pairs such as { (1, 2), (3, 4), (5, 5)}
Like a relation, a function has a domain and range made up of the x+and y values of ordered pairs.
In mathematics, what distinguishes a function from a relation is that each+x value in a function has one and only+ONE y-value.
Since relation (1, 2), (3, 4), (5, 5) has ONLY+ONE+y value for each+x+value, this relation IS a function.