Prentice Hall Algebra 2

3-4 Linear Programming

Objective

To solve problems using linear programming

A solve it problem with Serena.
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In the Solve It, you maximized your tomato production given some limits, or constraints. Linear programming is a method for finding a minimum or maximum value of some quantity, given a set of constraints.

Essential Understanding Some real-world problems involve multiple linear relationships. Linear programming accounts for all of these linear relationships and gives the solution to the problem.

The constraints in a linear programming situation form a system of inequalities, like the one below. The graph of the system is the feasible region. It contains all the points that satisfy all the constraints.

left brace . table with 4 rows and 1 column , row1 column 1 , x greater than or equal to 2 , row2 column 1 , y greater than or equal to 3 , row3 column 1 , y less than or equal to 6 , row4 column 1 , x plus y less than or equal to 10 , end table

A shaded quadrilateral on a graph represents the feasible region. The vertices are at (2, 6), (4, 6), (7, 3), and (2, 3). All points are approximate.

The quantity you are trying to maximize or minimize is modeled with an objective function. Often this quantity is cost or profit. Suppose the objective function is C = 2x + y.

Graphs of the objective function for various values of C are parallel lines. Lines closer to the origin represent smaller values of C.

The graphs of the equations 7 = 2x + y and 17 = 2x + y intersect the feasible region at (2, 3) and (7, 3). These vertices of the feasible represent the least and the greatest values for the objective function.

A shaded quadrilateral on a graph with vertices (2, 6), (4, 6), (7, 3), and (2, 3). A line, 7 equals 2x plus y, falls through (1, 5) and (2, 3). A second line, 17 equals 2x plus y, falls through (6, 7) and (7, 3).


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Table of Contents

Prentice Hall Algebra 2 Chapter 1 Expressions, Equations, and Inequalities Chapter 2 Functions, Equations, and Graphs Chapter 3 Linear Systems Chapter 4 Quadratic Functions and Equations Chapter 5 Polynomials and Polynomial Functions Chapter 6 Radical Functions and Rational Exponents Chapter 7 Exponential and Logarithmic Functions Chapter 8 Rational Functions Chapter 9 Sequences and Series Chapter 10 Quadratic Relations and Conic Sections Chapter 11 Probability and Statistics Chapter 12 Matrices Chapter 13 Periodic Functions and Trigonometry Chapter 14 Trigonometric Identities and Equations Skills Handbook English/Spanish Illustrated Glossary Selected Answers Index Acknowledgments