To check if a relation is a function, given a mapping diagram of the relation, use the following criterion: If each input has only one line connected to it, then the outputs are a function of the inputs.
Answer:
y-intercept is 30
Step-by-step explanation:
Given the model 
comparing this model to the equation of a straight lines we can get the y- intercept
The y- intercept is 30 which is the constant factor and it describes to us about the one-time registration fee of $30.
Answer:
[-9,∞)
Step-by-step explanation:
Answer:
y = 3x + 8
Step-by-step explanation:
y = mx + b
m is the slope
b is the y intercept
