Question

Which of the following is a function? A. {(1,1), (2,5), (-2,5), (1,-1)} B. {(-1,1), (-2,2), (-3,3), (-4,4)} C. {(-1,1), (-1,2), (-1,3), (-1,4)} D. {(-1,1), (-2,1), (-1,3), (-4,1)}

Answer 1

Hey!
So a function can not have the domain(the x coordinate) repeated in the whole function.
So that eliminates A because 1 is repeated
It eliminates C because -1 is repeated
It also eliminates D because -1 is repeated
So the answer is B!
Hope this helps!