<< Chapter < Page Chapter >> Page >

Another type of system of linear equations is an inconsistent system , which is one in which the equations represent two parallel lines. The lines have the same slope and different y- intercepts. There are no points common to both lines; hence, there is no solution to the system.

Types of linear systems

There are three types of systems of linear equations in two variables, and three types of solutions.

  • An independent system    has exactly one solution pair ( x , y ) . The point where the two lines intersect is the only solution.
  • An inconsistent system    has no solution. Notice that the two lines are parallel and will never intersect.
  • A dependent system    has infinitely many solutions. The lines are coincident. They are the same line, so every coordinate pair on the line is a solution to both equations.

[link] compares graphical representations of each type of system.

Given a system of linear equations and an ordered pair, determine whether the ordered pair is a solution.

  1. Substitute the ordered pair into each equation in the system.
  2. Determine whether true statements result from the substitution in both equations; if so, the ordered pair is a solution.

Determining whether an ordered pair is a solution to a system of equations

Determine whether the ordered pair ( 5 , 1 ) is a solution to the given system of equations.

x + 3 y = 8 2 x 9 = y

Substitute the ordered pair ( 5 , 1 ) into both equations.

( 5 ) + 3 ( 1 ) = 8               8 = 8 True 2 ( 5 ) 9 = ( 1 )             1=1 True

The ordered pair ( 5 , 1 ) satisfies both equations, so it is the solution to the system.

Got questions? Get instant answers now!
Got questions? Get instant answers now!

Determine whether the ordered pair ( 8 , 5 ) is a solution to the following system.

5 x −4 y = 20 2 x + 1 = 3 y

Not a solution.

Got questions? Get instant answers now!

Solving systems of equations by graphing

There are multiple methods of solving systems of linear equations. For a system of linear equations    in two variables, we can determine both the type of system and the solution by graphing the system of equations on the same set of axes.

Solving a system of equations in two variables by graphing

Solve the following system of equations by graphing. Identify the type of system.

2 x + y = −8 x y = −1

Solve the first equation for y .

2 x + y = −8 y = −2 x −8

Solve the second equation for y .

x y = −1 y = x + 1

Graph both equations on the same set of axes as in [link] .

The lines appear to intersect at the point ( −3, −2 ) . We can check to make sure that this is the solution to the system by substituting the ordered pair into both equations.

2 ( −3 ) + ( −2 ) = −8                   −8 = −8 True    ( −3 ) ( −2 ) = −1                   −1 = −1 True

The solution to the system is the ordered pair ( −3, −2 ) , so the system is independent.

Got questions? Get instant answers now!
Got questions? Get instant answers now!

Solve the following system of equations by graphing.

   2 x 5 y = −25 4 x + 5 y = 35

The solution to the system is the ordered pair ( −5 , 3 ) .

Got questions? Get instant answers now!

Can graphing be used if the system is inconsistent or dependent?

Yes, in both cases we can still graph the system to determine the type of system and solution. If the two lines are parallel, the system has no solution and is inconsistent. If the two lines are identical, the system has infinite solutions and is a dependent system.

Questions & Answers

what is biology
Hajah Reply
the study of living organisms and their interactions with one another and their environments
AI-Robot
what is biology
Victoria Reply
HOW CAN MAN ORGAN FUNCTION
Alfred Reply
the diagram of the digestive system
Assiatu Reply
allimentary cannel
Ogenrwot
How does twins formed
William Reply
They formed in two ways first when one sperm and one egg are splited by mitosis or two sperm and two eggs join together
Oluwatobi
what is genetics
Josephine Reply
Genetics is the study of heredity
Misack
how does twins formed?
Misack
What is manual
Hassan Reply
discuss biological phenomenon and provide pieces of evidence to show that it was responsible for the formation of eukaryotic organelles
Joseph Reply
what is biology
Yousuf Reply
the study of living organisms and their interactions with one another and their environment.
Wine
discuss the biological phenomenon and provide pieces of evidence to show that it was responsible for the formation of eukaryotic organelles in an essay form
Joseph Reply
what is the blood cells
Shaker Reply
list any five characteristics of the blood cells
Shaker
lack electricity and its more savely than electronic microscope because its naturally by using of light
Abdullahi Reply
advantage of electronic microscope is easily and clearly while disadvantage is dangerous because its electronic. advantage of light microscope is savely and naturally by sun while disadvantage is not easily,means its not sharp and not clear
Abdullahi
cell theory state that every organisms composed of one or more cell,cell is the basic unit of life
Abdullahi
is like gone fail us
DENG
cells is the basic structure and functions of all living things
Ramadan
What is classification
ISCONT Reply
is organisms that are similar into groups called tara
Yamosa
in what situation (s) would be the use of a scanning electron microscope be ideal and why?
Kenna Reply
A scanning electron microscope (SEM) is ideal for situations requiring high-resolution imaging of surfaces. It is commonly used in materials science, biology, and geology to examine the topography and composition of samples at a nanoscale level. SEM is particularly useful for studying fine details,
Hilary
cell is the building block of life.
Condoleezza Reply
Got questions? Join the online conversation and get instant answers!
Jobilize.com Reply

Get Jobilize Job Search Mobile App in your pocket Now!

Get it on Google Play Download on the App Store Now




Source:  OpenStax, Algebra and trigonometry. OpenStax CNX. Nov 14, 2016 Download for free at https://legacy.cnx.org/content/col11758/1.6
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Algebra and trigonometry' conversation and receive update notifications?

Ask