Question

For Items 7-9, two relations are given. One relation is a function and one is not. Identify each and explain. 7. {(5,-2), (-2,5), (2, -5), (-5,2)} {(5,-2), (-2,5), (5,2), (-5, 2)}

Answer 1

#Relation 1 is a function, for each value of x, there is a corresponding value of Y. Also there's no element in the x, without corresponding values in Y.So this is a Function

1) The easiest way to make it, is by sketching it a diagram.

Let's do this

For the 1st Relation:

As we can see, for each value of x, there is a corresponding value of Y. Also there's no element in the x, without corresponding values in Y.So this is a Function

#2 Relation

Since for 5 there are 2 corresponding values this can't be a function. Because in a function one value in the domain can only relate to another only one value in the Range.