Which equation best represents the diagram below?

Question

A green line with the number one and a blue line with the number 3 lie above a black line.

(1 point)
Responses

n-1 = 3
n-1 = 3

3-1 = n
3-1 = n

n+3 = 1
n+3 = 1

3n = 1

Answer 1

3-1 = n