
Algebra PreAlgebra and Basic Algebra Math Forum 
 LinkBack  Thread Tools  Display Modes 
September 20th, 2011, 05:56 AM  #1 
Newbie Joined: Sep 2011 Posts: 9 Thanks: 0  Linear equation in three variables
What is the value of “y” in the following system of equations? x + y + z = 75 ; 2x + y – z = 15 a. 0 b. 5 c. 15 d. 60 
September 20th, 2011, 08:10 AM  #2 
Global Moderator Joined: Dec 2006 Posts: 20,469 Thanks: 2038 
Is something mistyped or omitted? The equations imply that y = 30 + x/2 = 45  z/3.

September 20th, 2011, 12:42 PM  #3  
Global Moderator Joined: May 2007 Posts: 6,730 Thanks: 689  Re: Linear equation in three variables Quote:
 
September 20th, 2011, 03:31 PM  #4 
Global Moderator Joined: Dec 2006 Posts: 20,469 Thanks: 2038 
With only the two equations, y can't be calculated, but you can calculate 3x + 2z.

September 20th, 2011, 10:38 PM  #5 
Newbie Joined: Sep 2011 Posts: 9 Thanks: 0  Re: Linear equation in three variables
This is it, word for word. Thanks anyway. 

Tags 
equation, linear, variables 
Thread Tools  
Display Modes  

Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
various linear equations with various variables..  Dreamyvarela  Applied Math  1  January 8th, 2014 02:15 PM 
Dummy Variables (Multiple Linear Regression)  under72  Linear Algebra  0  November 11th, 2011 05:51 AM 
Dummy Variables (Multiple Linear Regression)  under72  Advanced Statistics  0  November 10th, 2011 05:26 PM 
Systems of linear equations in two variables  maxpalme  Algebra  1  April 2nd, 2009 10:33 AM 
Systems of linear equations in two variables  maxpalme  Abstract Algebra  1  December 31st, 1969 04:00 PM 