Answer: First and third
Step-by-step explanation:
- A function is a special kind of relation between two variable such that each input corresponds to exactly one output.
In the given pictures, the first and third picture are representing function because each input corresponds to exactly one output.
In second and fourth picture one input value corresponds to two output values.
i.e. a corresponds to 25 and 55 and x corresponds to 7 and 5 in output.
