The discontinuities are x=-4. Because it is a fraction, you cannot divide by zero so if the denominator is set to equal zero, which it will if x=-4, the function will be be undefined
Add all the number then multiply by 1,000
The cost per unit of the auto shop function is the slope of the function
87 represents the slope and the cost per tire purchased
The function is given as:

A linear function is represented as:

Where:
m represents the slope or the unit rate.
So, by comparison:

This means that 87 represents the slope and the cost per tire purchased
Read more about slopes at:
brainly.com/question/18576224
Dividing by a fraction means the same as multiplying by its reciprocal.
In other words, change the division sign to multiplication
and flip or take the reciprocal of the second fraction.
So we can rewrite 2/13 ÷ 1/6 as 2/13 × 6/1.
Now multiply across the numerators and denominators to get 12/13.