A graph is shown. How do you determine if this is a function or not? Is this a function. Help please

Not a function

Step-by-step explanation:

we see on this graph,

(1,2) and (1,7)

we have two of the same x points, when put on a graph, that would be having 2 of the same inputs.

which always means it's not a function.

okay wait before i answer, is this for your points on a graph?

i think it is everything has to equal 180 so, if i correct 4=c. 6=d. 8=a. 7=b. and the last question would be c. because they are parallel lines and they are congruent.

step-by-step explanation:

the reason everything has to equal to 180 is because that is how it works. i'm guessing that is its rule. 4 and 8 are congruent and parallel so, that would be 30+30 because they have the same number. it would equal 60. 6 and 7 are congruent and parallel so, that would be 30+30 because they have the same number. it would equal 60. 60+60 is 180. so, now you have your answer