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Solving a system of equations?

Show step by step how:

Equation 1: x[(1/z) + 1] - y(1/z) - 1/z = y

Equation 2: y[(1/z) + z] - x(1/z) = -x

becomes:

y = [-z + 1]/[z(z^2 + 2z +1)]

Hint: Express equation 2 in terms of x and plug into equation 1.

Update:

My attempt at isolating x in equation 2:

y[(1/z) + z] - x(1/z) = -x

y[(1/z) + z] = -x + x(1/z)

y[(1/z) + z] = x[ -1 + (1/z)]

y[(1/z) + z] = x[(1/z) - 1]

y[(1/z) + z]/[(1/z) - 1] = x

Update 2:

I'm going to leave it to Yahoo Answers users to do the rest, it's "just algebra" so you guys can handle it. Thanks.

3 Answers

Relevance
  • ?
    Lv 7
    1 year ago

    Equation 1:

    x[(1/z) + 1] - y(1/z) - 1/z = y     

    Equation 2:

    y[(1/z) + z] - x(1/z) = -x     

    becomes:     

    y = [-z + 1]/[z(z^2 + 2z +1)]     

    Hint: Express equation 2 in terms of x and plug into equation 1.

    1. 

    My attempt at isolating x in equation

    2: 

    y[(1/z) + z] - x(1/z) = -x   

    y[(1/z) + z] = -x + x(1/z)   

    y[(1/z) + z] = x[ -1 + (1/z)]   

    y[(1/z) + z] = x[(1/z) - 1]   

    y[(1/z) + z]/[(1/z) - 1] = x  

  • david
    Lv 7
    1 year ago

    Equation 2: y[(1/z) + z] - x(1/z) = -x  <<<  use the 'hint' ... solve fr x

      y[(1/z) + z] =  -x + x(1/z)

    x[(1/z) - 1]  =  y[(1/z) + z]

       x = y[(1/z) + z] / [(1/z) - 1]

      =====  now plug into eq 1

      Equation 1: x[(1/z) + 1] - y(1/z) - 1/z = y

       y[(1/z) + z] / [(1/z) - 1][(1/z) + 1] - y(1/z) - 1/z = y

      ...  from here do a lot of algebra steps t solve for y

     It is just algebra .. I leave the rest for you

  • ?
    Lv 7
    1 year ago

    So, start by applying their hint. Isolating x in the 2nd eqs gives x = ?

    Answer that & we will proceed. 

    OK. Now just plug it into the 1st eqs to get

    y[(1/z) + z] / [(1/z) - 1][(1/z) + 1] - y(1/z) - 1/z = y

    Now, just work at it to get it to the desired form.

    Start by isolating y. A little more simplification leads to the desired form.

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