The graph of y = f(x) is shown below. Find f(4).

Hi! I hope this answer helps you.

In mathematics, the vertical line test is a visual way to determine if a curve is a graph of a function or not. A function can only have one output, y, for each unique input, x.

any vertical line in the plane can intersect the graph of a function at most once.

HOW TO DO THIS

take your pencil and place it on your paper vertically (up and down direction)

move the pencil across the paper to the right

if the pencil crosses more than two points on the line it is not a function

the first problem would be a function

the second problem would be a function

the third problem would not be a function

hope this helps