Which one is a function?

Question

{(7,5),(-6,0),(2,3)}

{7,-6,2,-7}

I think its the first one.

Answer 1

The vertical line rule: If you graph a
function and draw a vertical line through it, it will intersect the graph
at only one point.

If you draw a vertical line through the
graph of an X-Parabola, it will intesect at two points. There, the
X-parabola is not a function.

Yes, your answer is correct!