Select the lines that represent functions

B,D and E are functions.

Step-by-step explanation:

" A function is a process or a relation that associates each element x of a set X, the domain of the function, to a single element y of another set Y (possibly the same set), the codomain of the function "

From the graph we can also check that any line passing through the domain and parallel to co-domain should intersect the graph exactly once.

Clearly from the graph of the functions we could see that:

Graph A:

Has many images corresponding to x= -6.

Hence, A is not a function.

Graph B:

B is a function as corresponding to every point in domain the image is unique. Also by making a line passing through the domain and parallel to the codomain the line intersect the graph exactly at one point.

Graph C:

C is not a function as it has two images for some points.

Graph D:

D is a function as it has unique image corresponding to every x-value.

Graph E:

E is also a function as it has unique image corresponding to every x-value.