Determine which relation is a function.

- gabbyalicorn

Determine which relation is a function.

- Stacey Warren - Expert brainly.com

Hey! We 've verified this expert answer for you, click below to unlock the details :)

- jamiebookeater

I got my questions answered at brainly.com in under 10 minutes. Go to brainly.com now for free help!

- gabbyalicorn

##### 1 Attachment

- ♪Chibiterasu

In a function, x values will never repeat.

- ♪Chibiterasu

There will only be one output for each input.

Looking for something else?

Not the answer you are looking for? Search for more explanations.

## More answers

- gabbyalicorn

All the coords look like they are on both x and y axis'

- gabbyalicorn

The only one I can sort of see correct is B...

- ♪Chibiterasu

It's not x-intercept it's just general x value. The wrong ones have points on the same x value. For isntance, in B, two points share the x value of positive 2.

- ♪Chibiterasu

|dw:1449890861658:dw|

- gabbyalicorn

Hmm, okay.

- ♪Chibiterasu

That's the key, if you see a vertical line like that with two points, it has more than one x value making it not a function.

- gabbyalicorn

It can't be slanted, either?

- ♪Chibiterasu

Just vertical lines. Look at each graph and see if two points are on the same vertical line, which means they share x values.

- gabbyalicorn

I don't really see any other vertical lines. Just slanted ones now. But at least we ruled out B.

- ♪Chibiterasu

I don't think you understand. Look at the points.|dw:1449891083046:dw|

- ♪Chibiterasu

Take the first line. I drew a red line through them because they form a vertical line. If you type out the coordinates it makes sense
(-2, 1)
(-2, -2)
They share an x of -2

- ♪Chibiterasu

And the second red line as well
(2, 0)
(2, -2)
they share an x value of 2
functions will not repeat x values

- gabbyalicorn

Well, I'm still not sure about this. But maybe this could help you to help me. This is how I look at the options.

##### 1 Attachment

- ♪Chibiterasu

dont draw slanted lines, only draw vertical lines

- ♪Chibiterasu

vertical lines = x values

- gabbyalicorn

The only vertical line I see are for B and C. The only difference between the both of them is that B has two vertical lines and C has one. Although, I am now realizing that C could be the answer that matches what you told me.

- ♪Chibiterasu

Any vertical lines means its not a function. They don't repeat x values so vertical lines automatically rule out.

- gabbyalicorn

Oh. ._. I see. So now that leaves us with just A and D. A seems like a reasonable answer because they are showing two slanted lines.

- ♪Chibiterasu

Slanted lines dont amtter. Only verticals. We are focusing purely on verticals.
Let me explain it:
x = 2
This expression means ALL VALUES with a value of x. This make a vertical line on the x-axis on 2. The line has all values that have 2 as their x-coordinate.|dw:1449891697274:dw|

- ♪Chibiterasu

Remember what I said: Functions NEVER repeat x values, which is why vertical lines are so important to understand

- gabbyalicorn

But I thought we were ruling out vertical lines. "Any vertical lines means its not a function. They don't repeat x values so vertical lines automatically rule out." I must have interpreted this wrong, then.

- ♪Chibiterasu

Exactly. Any poitns on the vertical line means it has that x-value. If there is a vertical line which contains MORE THAN 1 POINT it means its not a function.

- ♪Chibiterasu

which is why this is so important to look at
|dw:1449891856270:dw|

- gabbyalicorn

But we were only ruling out the vertical lines. That's why I thought A was a good option, because on option A, they were only slanted/diagonal lines.

- ♪Chibiterasu

Ok listen, the slanted lines literally mean nothing and are not important. Look at each graph. Points that lie on the same x value (vertical) make it not a function

- gabbyalicorn

Ok, got it.

- ♪Chibiterasu

|dw:1449892120656:dw|

- gabbyalicorn

So, basically we need to find x=-2 stuff...

- ♪Chibiterasu

x = anything
anything that shares x value makes it so that its not a function
its no that hard to understand

- gabbyalicorn

Maybe I'm just thinking about it too hardly. Give me a minute.

- ♪Chibiterasu

yeah its pretty simple dont complicate urself

- ♪Chibiterasu

sorry if i come off a bit grumpy, its 11 pm over here xD

- gabbyalicorn

Oh, okay...I totally understand. It's 7:51PM over here. Sorry if I'm taking a long time to understand it. Then I'd narrow my options down to B and C.

- ♪Chibiterasu

Those are the ones we ruled out because there are points that >>share x-values<<

- gabbyalicorn

Okay, then I rule out D too.

- ♪Chibiterasu

woops, caps

- ♪Chibiterasu

do you see any poitns on d that share x values

- gabbyalicorn

kind of....

- ♪Chibiterasu

|dw:1449892479156:dw|

- ♪Chibiterasu

Ok let me try something
look at every point on graph a and then go down the line on that point. if it meets with any other points, its not a function cuz theres more than 1 point on the same x value

- gabbyalicorn

Okay, well I think it's D now. :3

- ♪Chibiterasu

yeah LOL

- ♪Chibiterasu

just to make sure, why did you choose that one?

- ♪Chibiterasu

it is d but i just wanna make sure u understand the point kinda

- gabbyalicorn

I chose that one because non of the points were on the same point. Here's my work.

##### 1 Attachment

- ♪Chibiterasu

this is what i was trying to explain
|dw:1449893004842:dw|

- ♪Chibiterasu

the last thing says:
not able to make vertical line; it is a function!

- gabbyalicorn

I get it now. :) Thank you so much! Also, thanks for not giving up on me/leaving me out of the blue.

- ♪Chibiterasu

haha np, im gonna go to bed now my eyes hurt :D

- gabbyalicorn

Okay, get a lot of rest. :)

- ♪Chibiterasu

thanks xD

- gabbyalicorn

No problem. ;}

Looking for something else?

Not the answer you are looking for? Search for more explanations.