Math

Solving systems of equations with three variables?
What is the solution to the system?
1] x+y+z=-3
2] 3y-z=4
3] 2x-y-2z=-5

  1. 👍 0
  2. 👎 0
  3. 👁 48
asked by Kori
  1. equation 2 only has two variables so use it to solve for z
    z = (3y-4)

    now substitute (3y-4) for z in the other 2 equations

    x+y+(3y-4)=-3
    2x-y-2(3y-4)=-5

    1 x + 4 y = 1
    2 x - 7 y = -13

    2 x + 8 y = 2
    2 x - 7 y = -13
    ----------------
    0 x +15 y = 15

    y = 1
    etc

    1. 👍 0
    2. 👎 0
    posted by Damon

Respond to this Question

First Name

Your Response

Similar Questions

  1. pre calculus

    Create systems of equations in two variables that have (a) no solution, (b) one distinct solution, and (c) infinite solutions. Show that each system has the indicated number of solutions by using a graph or solving the system.

    asked by Anonymous on November 29, 2016
  2. Math

    PLEASE CHACK MY ANSWER!!! Discussion for Applications of Linear Systems When solving a system of equations, how do you determine which method to use? My answer: I determine which method to use by looking at the equations. If both

    asked by Matthew on December 15, 2016
  3. math help pls pls

    Two systems of equations are shown below: System A 6x + y = 2 −x − y = −3 System B 2x − 3y = −10 −x − y = −3 Which of the following statements is correct about the two systems of equations? The value of x for

    asked by Oscar on December 21, 2015
  4. math

    How do you solve system of equations and tell if they're consistant and independant,consistant and dependent,and inconsistant? If you find no solutions then the system is inconsistent. Suppose you have N variables and M equations

    asked by maddie on July 27, 2007
  5. Alg 2

    Today we learned how to solve systems of equations with 3 variables, however my teacher didn't go over how to do a problem where not every single equation in the system has the 3 variables. Can someone point me to a place that

    asked by john on October 5, 2012
  6. Algebra 2

    Solving Systems of Equations in Three Variables: 3x+4y+z=1 x+3y-z=-2 -2x+y-2z=-5 Please show work

    asked by Stephy on November 9, 2014
  7. Algebra 2

    Solving Systems of Equations in Three Variables: 3x+3y-z=-3 -2x-3y+2z=3 x-6y+3z=0 PLease show work

    asked by Stephy on November 9, 2014
  8. math

    two systems of equations are giving below for each system choosethe best description of its solution if applicable give solution x+4y=8 -x-4y= -8 choose which one this problem fit in 1)the system has no solution 2) the system has

    asked by sw on March 7, 2013
  9. quick question regarding equations

    I know there are methods out there but what do you think is the best or easiest method(s) of solving a system of equations. Depends on the coefficients of the equation. If in one of the equations I can solve for one of the

    asked by Shawn on August 14, 2007
  10. Algebra

    Solving systems of linear equations in 3 variables... 1) 3x-2y+2z=1 2) 2x+5y-5z=7 3) 4x-3y+z=-3 I combined 1 and 3 to get -5x+4y=7 And then i combined 2 and 3 to get -13y+11z=-17. Can that be right? how would you combine those two

    asked by Max on November 13, 2010

More Similar Questions