EDIT#2: Yes, I'm crazy! This IS a function. Thanks for beating the correct logic into me everyone!
I'm using a website provided by my algebra textbook that has questions and answers. It has the following question:
Determine whether the following relation represents a function: $\{(-9,-3),(2,-1),(7,7),(-1,-1)\}$
I answered NO, it is not a function but the website says it is. Am I wrong? If so, what am I missing?
EDIT: I was given the following definition in class:
Function: A function is a rule which assigns to each X, called the domain, a unique y, called the range.
My instructor also said that if you plot the points you can tell if it is not a function if it fails the vertical line test. Here is the graph of the above points, and for example it would fail the vertical line test if I drew one on x = 1, right?
Thanks! Jason