Answer:
Rate of change for the linear relationship modeled is 
Step-by-step explanation:
As the there is a linear relationship in the points, so all these points will be on a single straight line. Hence the slope will be same throughout all the points.
We know that, the slope of the line joining (x₁, y₁) and (x₂, y₂) is,

Putting the points as (-1, 10) and (1, 9), we get



Rate of change is the slope of the line joining all these points.
Answer:
8
Step-by-step explanation:
To find the mean, you add up all the numbers and divide it by the total number of numbers. So 4+5+7+8+11+13 is 48. There are 6 numbers. So 48/6=8.
Answer:
20
Step-by-step explanation:
420-400=20