00:01
The quick explanation for this one is there's only one graph that passes the vertical line test.
00:06
And the reason why we have the vertical line test for if something is a function, i'll jot this in a different color.
00:16
If there's a function, then the y values cannot repeat.
00:21
So as you go through the options, i'll talk about what the y values are, well, i guess i should say the x values, but it's very.
00:33
Vertical line, x values cannot repeat.
00:36
So as you go through each one of these, so the very first curve is like this, well, if you have a vertical line, say right here, maybe it would be best if i did x equals zero, you can see that there's two ordered pairs that have x equals zero, like zero, and i'm just making up a point zero two, and the x values repeat.
00:57
So that is not correct.
00:59
So i can go to the next one, which has a lot of times where your vertical line test has failed, but there's just two points where the x values repeat.
01:10
So it's wrong.
01:11
Letter c is actually your correct answer.
01:13
So let me do this one in green...