Determine which of the following terms is a function: a. (1,2) (2,4) (3,5) c. (1,2) (2,4) (2,6) b. (1,2) (2,3) (1,5) d. (1,2) (3,5) (3,7)

In a function, X does not repeat.
Your answer is A.

a (1,2) (2,4) (3,5)
there are different x values for
each point, so this IS A FUNCTION.

b. (1,2) (2,3) (1,5)
there are two values of x being 1,
so this is NOT A FUNCTION.

c. (1,2) (2,4) (2,6) 
there are two values of x being 2
so this is NOT A FUNCTION.

d. (1,2) (3,5) (3,7)there are two values of x being 3,
so this is NOT A FUNCTION.

hope this helps and have a great day!