System of three linear equations with unknown constant












1












$begingroup$


I have a linear system with three equations:



$$begin{align}
x + y + z &= 3a\
x + 2y + (a+2)z &= a\
x - (a+1)y - z &= 0
end{align}$$



I want to find values for a where the system is inconsistent in addition to the values of $x, y, z$ and $a$ for where the system is consistent.



How should one approach a problem like this?



Thanks in advance.










share|cite|improve this question











$endgroup$

















    1












    $begingroup$


    I have a linear system with three equations:



    $$begin{align}
    x + y + z &= 3a\
    x + 2y + (a+2)z &= a\
    x - (a+1)y - z &= 0
    end{align}$$



    I want to find values for a where the system is inconsistent in addition to the values of $x, y, z$ and $a$ for where the system is consistent.



    How should one approach a problem like this?



    Thanks in advance.










    share|cite|improve this question











    $endgroup$















      1












      1








      1





      $begingroup$


      I have a linear system with three equations:



      $$begin{align}
      x + y + z &= 3a\
      x + 2y + (a+2)z &= a\
      x - (a+1)y - z &= 0
      end{align}$$



      I want to find values for a where the system is inconsistent in addition to the values of $x, y, z$ and $a$ for where the system is consistent.



      How should one approach a problem like this?



      Thanks in advance.










      share|cite|improve this question











      $endgroup$




      I have a linear system with three equations:



      $$begin{align}
      x + y + z &= 3a\
      x + 2y + (a+2)z &= a\
      x - (a+1)y - z &= 0
      end{align}$$



      I want to find values for a where the system is inconsistent in addition to the values of $x, y, z$ and $a$ for where the system is consistent.



      How should one approach a problem like this?



      Thanks in advance.







      linear-algebra systems-of-equations






      share|cite|improve this question















      share|cite|improve this question













      share|cite|improve this question




      share|cite|improve this question








      edited Dec 16 '18 at 15:14









      mrtaurho

      5,74551540




      5,74551540










      asked Dec 16 '18 at 14:45









      Olof AlmqvistOlof Almqvist

      82




      82






















          1 Answer
          1






          active

          oldest

          votes


















          0












          $begingroup$

          With $$z=x-(a+1)y$$ we get
          $$2x+y-(a+1)y=3a$$
          and
          $$2x-ay=3a$$
          eliminating $x$ we obtain
          $$-frac{3a(a+3)}{2}y=-frac{3a(a+3)}{2}$$
          Now you can do the rest!






          share|cite|improve this answer









          $endgroup$













          • $begingroup$
            Thanks for your help Dr. Graubner! :)
            $endgroup$
            – Olof Almqvist
            Dec 16 '18 at 17:34











          Your Answer





          StackExchange.ifUsing("editor", function () {
          return StackExchange.using("mathjaxEditing", function () {
          StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
          StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
          });
          });
          }, "mathjax-editing");

          StackExchange.ready(function() {
          var channelOptions = {
          tags: "".split(" "),
          id: "69"
          };
          initTagRenderer("".split(" "), "".split(" "), channelOptions);

          StackExchange.using("externalEditor", function() {
          // Have to fire editor after snippets, if snippets enabled
          if (StackExchange.settings.snippets.snippetsEnabled) {
          StackExchange.using("snippets", function() {
          createEditor();
          });
          }
          else {
          createEditor();
          }
          });

          function createEditor() {
          StackExchange.prepareEditor({
          heartbeatType: 'answer',
          autoActivateHeartbeat: false,
          convertImagesToLinks: true,
          noModals: true,
          showLowRepImageUploadWarning: true,
          reputationToPostImages: 10,
          bindNavPrevention: true,
          postfix: "",
          imageUploader: {
          brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
          contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
          allowUrls: true
          },
          noCode: true, onDemand: true,
          discardSelector: ".discard-answer"
          ,immediatelyShowMarkdownHelp:true
          });


          }
          });














          draft saved

          draft discarded


















          StackExchange.ready(
          function () {
          StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3042685%2fsystem-of-three-linear-equations-with-unknown-constant%23new-answer', 'question_page');
          }
          );

          Post as a guest















          Required, but never shown

























          1 Answer
          1






          active

          oldest

          votes








          1 Answer
          1






          active

          oldest

          votes









          active

          oldest

          votes






          active

          oldest

          votes









          0












          $begingroup$

          With $$z=x-(a+1)y$$ we get
          $$2x+y-(a+1)y=3a$$
          and
          $$2x-ay=3a$$
          eliminating $x$ we obtain
          $$-frac{3a(a+3)}{2}y=-frac{3a(a+3)}{2}$$
          Now you can do the rest!






          share|cite|improve this answer









          $endgroup$













          • $begingroup$
            Thanks for your help Dr. Graubner! :)
            $endgroup$
            – Olof Almqvist
            Dec 16 '18 at 17:34
















          0












          $begingroup$

          With $$z=x-(a+1)y$$ we get
          $$2x+y-(a+1)y=3a$$
          and
          $$2x-ay=3a$$
          eliminating $x$ we obtain
          $$-frac{3a(a+3)}{2}y=-frac{3a(a+3)}{2}$$
          Now you can do the rest!






          share|cite|improve this answer









          $endgroup$













          • $begingroup$
            Thanks for your help Dr. Graubner! :)
            $endgroup$
            – Olof Almqvist
            Dec 16 '18 at 17:34














          0












          0








          0





          $begingroup$

          With $$z=x-(a+1)y$$ we get
          $$2x+y-(a+1)y=3a$$
          and
          $$2x-ay=3a$$
          eliminating $x$ we obtain
          $$-frac{3a(a+3)}{2}y=-frac{3a(a+3)}{2}$$
          Now you can do the rest!






          share|cite|improve this answer









          $endgroup$



          With $$z=x-(a+1)y$$ we get
          $$2x+y-(a+1)y=3a$$
          and
          $$2x-ay=3a$$
          eliminating $x$ we obtain
          $$-frac{3a(a+3)}{2}y=-frac{3a(a+3)}{2}$$
          Now you can do the rest!







          share|cite|improve this answer












          share|cite|improve this answer



          share|cite|improve this answer










          answered Dec 16 '18 at 14:47









          Dr. Sonnhard GraubnerDr. Sonnhard Graubner

          77.2k42866




          77.2k42866












          • $begingroup$
            Thanks for your help Dr. Graubner! :)
            $endgroup$
            – Olof Almqvist
            Dec 16 '18 at 17:34


















          • $begingroup$
            Thanks for your help Dr. Graubner! :)
            $endgroup$
            – Olof Almqvist
            Dec 16 '18 at 17:34
















          $begingroup$
          Thanks for your help Dr. Graubner! :)
          $endgroup$
          – Olof Almqvist
          Dec 16 '18 at 17:34




          $begingroup$
          Thanks for your help Dr. Graubner! :)
          $endgroup$
          – Olof Almqvist
          Dec 16 '18 at 17:34


















          draft saved

          draft discarded




















































          Thanks for contributing an answer to Mathematics Stack Exchange!


          • Please be sure to answer the question. Provide details and share your research!

          But avoid



          • Asking for help, clarification, or responding to other answers.

          • Making statements based on opinion; back them up with references or personal experience.


          Use MathJax to format equations. MathJax reference.


          To learn more, see our tips on writing great answers.




          draft saved


          draft discarded














          StackExchange.ready(
          function () {
          StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3042685%2fsystem-of-three-linear-equations-with-unknown-constant%23new-answer', 'question_page');
          }
          );

          Post as a guest















          Required, but never shown





















































          Required, but never shown














          Required, but never shown












          Required, but never shown







          Required, but never shown

































          Required, but never shown














          Required, but never shown












          Required, but never shown







          Required, but never shown







          Popular posts from this blog

          Willebadessen

          Ida-Boy-Ed-Garten

          Residenzschloss Arolsen