Answer:
y=f(x)
y=5x
y=3x
are examples of function
Step-by-step explanation:
definition of a function
if there is one to one relation between a relation
then it is defined as a function
for example
y=5x is a function
because when we put some value of x it gives back only one value of y as output.
y=±5x is not a function because one value of x gives two values(positive and negative) values of y hence not a function.