The line f(x) = x is graphed in the xy-coordinate plane.
How does the graph of the function f(x) + 1 compare to the graph of f(x)?

Please check the attached diagram.

Thus, we conclude that:

In the diagram,

The blue line indicates that the parent function has been shifted 1 unit upward.

Step-by-step explanation:

Let us recall some transformation knowledge.

We know that

if y = f(x), then y = f(x) + b simply means a transformation of (0, b).

In other words, if we add some constant let say 'b' in the output or y-value, the graph simply shifts upward by b units.

Given that

f(x) = x

so

f(x+1) = x+1 means the parent function f(x) = x has been shifted 1 unit upward.

Please check the attached diagram.

Thus, we conclude that:

In the diagram,

The blue line indicates that the parent function has been shifted 1 unit upward.