Chapter 2 – Linear Equations and Functions 2.2 – Linear Functions and Function Notation

In this section we will review: –Identifying, evaluating, and graphing linear functions

2.2 – Linear Functions and Function Notation Linear function – a function in the form y = mx + b, where m and b are constants –Linear functions have a variable to the first power By naming a function “f ”, it can be written using function notation –f (x) = mx + b –Read as: The value of f at x f of x

2.2 – Linear Functions and Function Notation In function notation, f (x) is used in the place of y. You may use letters other than f to name a function.

2.2 – Linear Functions and Function Notation Example 1 –Evaluate the function when x = -5 f (x) = x 2 + x + 4 g (x) = -4x – 6

2.2 – Linear Functions and Function Notation Example 2 –Graph f (x) = -x + 5

2.2 – Linear Functions and Function Notation Example 3 –Graph g (x) = 4x – 3.

2.2 – Linear Functions and Function Notation Example 4 –A cell phone company charges $15 per month plus $0.07 per minute for all calls. Write a function that models the monthly cost c for t minutes of calls. Graph the function.

2.2 – Linear Functions and Function Notation Example 5 –You buy a used car from a local dealership. You pay $1600 and agree to make payments of $200 per month for the next 3 years, at which time the car will be paid off. The function p (t ) = 200t models the total amount p that you have paid for the car after making payments for t months.

2.2 – Linear Functions and Function Notation Example 5 (cont) –p (t ) = 200t What is a reasonable domain? Graph p (t ) How much have you paid for the car after you have been making payments for 16 months? What is the total amount that you pay for the car?

2.2 – Linear Functions and Function Notation HOMEWORK Worksheet 2.2