Question

Determine which relation is a function.

A. {(–3, 2), (–1, 3), (–1, 2), (0, 4), (1, 1)}

B. {(–3, 2), (–2, 3), (–1, 1), (0, 4), (0, 1)}

C. {(–3, 3), (–2, 3), (–1, 1), (0, 4), (0, 1)}

D. {(–3, 2), (–2, 3), (–1, 2), (0, 4), (1, 1)}

Answer 1

Are you allowed only one answer?
Because I use a vertical line test and A was the only one that fail it.
A vertical line test is like:
http://upload.wikimedia.org/wikipedia/commons/f/fd/Vertical_line_test.png
If the pencil hits to points on a graph, it's NOT a function.
Here is A when I graphed it:
http://www.wolframalpha.com/share/img?i=d41d8cd98f00b204e9800998ecf8427esnkg2h6nf0&f=HBQTQYZYGY4TSM3BGZRTSZDGGEYDCM3EGQ2TMODCGNRTSNZTGFSAaaaa

See how it hits two points? Since it hit two points, it's NOT a function...

Answer 2

Well theres sopose to be one asnwer

Answer 3

Hehe, sorry then...
I dunno >.<

Answer 4

D

Answer 5

u sure? @LazyBoy

Answer 6

pretty sure

Answer 7

all you have to do is make sure that the first element within each of the ordered pair doesn't repeat.
ie in (a,b) a is what i'm talking about.
if you notice, D is the only option where this is true. everywhere else, one of the first elements repeats itself.