Applications of Linear Functions

Slope represents a rate of change. (Change in rise over change in run)

Which formula did the previous example use to solve?

The population of a city increased from 23,400 in 2008 to 27,800 in 2012. Find the change of population per year if we assume the change was constant from 2008 to 2012.

What was the function used to describe Marcus' song collection?

My first step is to use the slope formula $$m=\ \frac{y_{2\ }-y_1}{x_2-x_1}$$ to find the rate of cost per policy

How would I set that up?

To find the initial value (y - intercept) we will use the function $$I\left(t\right)=80n+b$$ and use one of our given ordered pairs, such as $$\left(760,\ 3\right)$$ and solve for $$b$$ .

Which is the correct set up?

Belinda's car needed repairs. The mechanic charged him $140 for the parts and an additional $48 an hour for labor. Write an equation that models this situation.

A man is climbing down from 100 feet high descending 30 feet per minute. Which function models his descent?

Derrick started a new job at McDonald's. He makes $10 per hour. Which graph models his total weekly earnings in terms of the number of hours he works?

Derrick started a new job at McDonald's. He makes $10 per hour. What is the independent variable?

Abby decides to get a magazine subscription. It costs her $2 per magazine plus an initial fee of $3. Define the variables