P. 102 15 – 60 5ths

APPLY LINEAR FUNCTIONS

X-axis time since purchase Y-axis value Use two intercepts (0, initial value) and

(time until value is zero, 0) to form line

A company buys a new company car for $28,000. The company will replace this new car in seven years.

a. Find the equation of the straight line depreciation.

b. Graph the line.

c. What is the “book-value” of the car after three years?

d. Interpret the slope of the line.

e. When will the book value of the car be $8000?

Equilibrium price – price at which supply is equal to demand.

Supply - The quantity supplied of a good is the amount of a product that a company is willing to make available for sale at a given price. The supply function is named S(p).

Demand - The quantity demanded of a good is the amount of a product that consumers are willing to purchase at a given price. The demand function is named D(p).

Suppose that the quantity supplied, S, and quantity demanded, D, of cellular telephones each month are given by the following functions:

S(p) = 60P – 900D(p) = -15p + 2850Where p is the price (in dollars) of the telephone.a. What is the equilibrium price?b. Determine the prices at which supply is greater

than demand. That is solve S(p) > D(p).c. Graph the supply and demand functions and

label the equilibrium price.

LINEAR REGRESSION

(a) Draw a scatter diagram of the data, treating on-base percentage as the independent variable.

(b) Use a graphing utility to draw a scatter diagram.

(c) Describe what happens to runs scored as the on-base percentage increases.

LINEAR – positive, negative, constant NONLINEAR

Eye-ball method Enter data into list Make scatterplot Select to “representative” points Find line using these two points

(a)Select two points and find an equation of the line containing the points.

(b) Graph the line on the scatter diagram obtained in the previous example.

Use the eye-ball method to find the line of best fit.

Enter data into listGo to STATGo to CALCGo to LINREG

(a) Use a graphing utility to find the line of best fit that models the relation between on-base percentage and runs scored.

(b) Graph the line of best fit on the scatter diagram obtained in the previous example.

(c) Interpret the slope.

(d) Use the line of best fit to predict the number of runs a team will score if their on-base percentage is 33.5.

Use your calculator to find the line of best fit.

Age (months)

Height (cm)

36 86

48 90

51 91

54 93

57 94

60 95