The points (−1, 2) and (−1, 1) satisfy a relation R, which of the following can we (definitely) conclude?

Select one:

a. R is a function

b. R is not a function

c. R is y=-1

d. R is x=-1

e. None of the above

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- Mar 28th 2013, 06:07 PMmathkid182help please-hard questionThe points (−1, 2) and (−1, 1) satisfy a relation R, which of the following can we (definitely) conclude?

Select one:

a. R is a function

b. R is not a function

c. R is y=-1

d. R is x=-1

e. None of the above

- Mar 28th 2013, 06:56 PMPazeRe: help please-hard question
This is not a hard question. Tell us what you have tried so far.

- Mar 28th 2013, 07:34 PMProve ItRe: help please-hard question
- Mar 28th 2013, 07:41 PMmathkid182Re: help please-hard question
not to worry sorry i figured out that because it has the same -1 on both plots it is not a function.

what about this one-

The points (1, 3) and (2, 3) satisfy a relation R, which of the following can we (definitely) conclude?

Select one:

a. R is a function

b. R is not a function

c. R is y=3

d. R is a straight line

e. None of the above

I know its a straight line and is function but neither answers are right? what would be the right answer? - Mar 28th 2013, 08:00 PMPazeRe: help please-hard question
- Mar 29th 2013, 01:56 AMemakarovRe: help please-hard question
- Mar 29th 2013, 04:48 AMRuunRe: help please-hard question
Suposse that your given ordered pairs belong to the cartesian product that defines a function. Then they will be in the form $\displaystyle (x,f(x))$. Now recall the definition of a function, in particular about the uniqueness about $\displaystyle f(x)$

- Mar 29th 2013, 06:46 AMHallsofIvyRe: help please-hard question
No, you

**don't**know either of those things. For example the relation containing pairs {(1, 3), (2, 3), (1, -3)} and y= x for x not equal to 1 or 2 is not a function nor a straight line but sastisfies the conditions. You seem to be under the impression that since we have both (1, 3) and (2, 3) we**must**have "y= 3" for all x. That is**possible**but not necessary. - Mar 29th 2013, 08:51 AMPazeRe: help please-hard question
- Mar 29th 2013, 09:47 AMemakarovRe: help please-hard question
- Mar 29th 2013, 09:58 AMPazeRe: help please-hard question
I don't understand. We have the points (1,3) and (2,3) and we are to conclude a relation between these points. y=3 in both points so how come this does not satisfy a 'relationship' between

**these two**points? Nobody said anything about all x. Or maybe I am misunderstanding? - Mar 29th 2013, 10:07 AMemakarovRe: help please-hard question
- Mar 29th 2013, 10:13 AMHartlwRe: help please-hard question