Which relation is not a function?

A

Step-by-step explanation: Notice that the input of nineteen outputs to 10 or 11. Remember that a function should have unique or non-repeating y-coordinates for every x-coordinate. Let me know if you need more clarifications.

i = 2 / - 5

step-by-step explanation:

evaluation of ( 2 - 4 ) ( p + q ) when p = 2 and q = 5 i, by putting values of p and q,                                                                    

b

step-by-step explanation:

a difference is the result of subtraction. while each of these expressions has subtraction in it, a difference will be the result when subtraction is the last operation applied in the order of operations for the expression. this means subtraction must be outside of the parenthesis. only b has this.