I'm also unsure what this question means, but maybe you can find some help here:
http://www.bing.com/search?q=example%20of%20a%20linear%20function%20on%20a%20graph&pc=cosp&ptag=D061515A213C8318C1&form=CONMHP&conlogo=CT3210127
which of the following represents a function on a line.
ellipse
circle
horizontal
vertical
Is the correct answer vertical?
2 answers
Thank you