Answer: 10
<u>Step-by-step explanation:</u>
varies directly means: 
Step 1: solve for k ⇒ 
Step 2: plug in the given value and k to solve for the missing value: 
42(5) = 21(x)

2(5) = x
10 = x
Answer:

Step-by-step explanation:
Given
See attachment for graph
Required
The unit cost
Pick any point on the dots of the graph; we have:

The unit cost is then calculated as:


Answer:
To get to -3 you can do 1+-4