Answer:
D. y = 12.5x + 15
Step-by-step explanation:
Using the values provided in the table, the only equation that would be valid would be the following...
y = 12.5x + 15
That is because if we substitute any value provided in the table for x , this equation will correctly output the y value shown in the table for the attached x-value. For example, in the table 5 nights (x = 5) should have a total cost of 77.5 (y = 77.5)... Therefore, if we substitute 5 for x in the function it should give us 77.5 which it does.
y = 12.5(5) + 15
y = 62.5 + 15
y = 77.5
All it takes for a relation to be a function is for each possible first number of a pair there's only one possible second number.
So if any of the sets has two pairs with the same first number, that one's not a function.
The last one has (3,2) and (3,5) so isn't a function.
Answer:
infinite: 4x + 14 = 2(2x+7)
none: 4x + 13 = 4x - 13