Answer:
(1,4) and (1,3), because they have the same X-value
Explanation:
A function is a set of ordered pairs which is related by an equation. A function cannot have a set of ordered pair with the same x coordinate, but it can have ordered pairs with repeated y values that is each x coordinate is unique and different.
The set of ordered pair (1,4) and (1,3) have the same X coordinate of 1, therefore it cannot be a function but (1,3) and (-1,3) can be represented as a function.
What should you use to turn the water off and open the door?
youn need to use your hands