Prentice Hall Algebra 1

4-3 Patterns and Nonlinear Functions

Quick Review

A nonlinear function is a function whose graph is not a line or part of a line.

Example

The area A of a square field is a function of the side length s of the field. Is the function linear or nonlinear?

Side Length (ft), s 10 15 20 25
Area open , ft squared , close comma  A 100 225 400 625

This graph is a curve that rises from approximately (0, 0) through (10, 100), (15, 225), (20, 400), and (25, 625).

Exercises

Graph the function shown by each table. Tell whether the function is linear or nonlinear.

  1. x y
    1 0
    2 1
    3 8
    4 20
  2. x y
    1 0
    2 4.5
    3 9
    4 13.5
  3. x y
    1 2
    2 6
    3 12
    4 72
  4. x y
    1 negative 2
    2 negative 9
    3 negative 16
    4 negative 23

4-4 Graphing a Function Rule

Quick Review

A continuous graph is a graph that is unbroken. A discrete graph is composed of distinct, isolated points. In a real-world graph, show only points that make sense.

Example

The total height h of a stack of cans is a function of the number n of layers of 4.5-in. cans used. This situation is represented by h equals 4.5 n .  Graph the function.

n h
0 0
1 4.5
2 9
3 13.5
4 18

This graph consists of a series of points at (0, 0), (1, 4.5), (2, 9), (3, 13.5), and (4, 18).

Exercises

Graph the function rule. Explain why the graph is continuous or discrete.

  1. Walnuts Your cost c to buy w pounds of walnuts at $6/lb is represented by c equals 6 w .
  2. Moving A truck originally held 24 chairs. You remove 2 chairs at a time. The number of chairs n remaining after you make t trips is represented by n equals 24 minus 2 t .
  3. Flood A burst pipe fills a basement with 37 in. of water. A pump empties the water at a rate of 1.5 in./h. The water level l, in inches, after t hours is represented by l equals 37 minus 1.5 t .
  4. Graph y equals negative vertical line x vertical line plus 2 .

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Table of Contents

Prentice Hall Algebra 1 Chapter 1 Foundations for Algebra Chapter 2 Solving Equations Chapter 3 Solving Inequalities Chapter 4 An Introduction to Functions Chapter 5 Linear Functions Chapter 6 Systems of Equations and Inequalities Chapter 7 Exponents and Exponential Functions Chapter 8 Polynomials and Factoring Chapter 9 Quadratic Functions and Equations Chapter 10 Radical Expressions and Equations Chapter 11 Rational Expressions and Functions Chapter 12 Data Analysis and Probability Skills Handbook Reference Visual Glossary Selected Answers Index Acknowledgments