Question:

Help to solve 2 questions (2x - 7)(x + 1) = 5 – x(1 – 2x) and (2x - 7)(x + 1) < 5 – x(1 – 2x)?

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Please show proper technique for me to accomplish this by myself next time, Thank You...

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  1. 1.

    (2x-7)(x+1) = 5-x(1-2x)

    2x^2 - 7x + 2x - 7 = 5 -x + 2x^2 (multiply out brackets)

    2x^2 -5x -7 = 5 -x +2x^2 (collect terms)

    -5x - 7 =5 - x

    -4x - 7 = 5

    -4x = 12

    x = -3

    2.

    (2x-7)(x+1) &lt; 5-x(1-2x)

    2x^2 -7x +2x - 7 &lt; 5-x+2x^2 (multiply out brackets)

    -4x &lt; 12  (collect terms)

    now divide both sides by -1 (remembering to change direction of)

    4x &gt; -12

    x &gt; -3


  2. I don&#039;t know how to write x squared ( x with the small 2 on top ) on the computer so i will use ^ between the x and the 2.

    2X^2 + 2X - 7X - 7= 5 - X + 2X^2

    -5X - 7 = 5 - X

    -4X = 12

    X = 12/-4

    X = -3

    2X^2 + 2X - 7X - 7 &lt; 5 - X +2X^2

    -5X - 7 &lt; 5-X

    -4X &lt; 12

    X &gt; 12/-4

    X &gt; -3

    NOTICE: the sign changes when you divide by a negative number.

    I didn&#039;t put all the step because I assume you have some knowledge of the problems and would understand. Also not knowing how to write the index is frustrating

  3. Equation 1

    (2x-7)(x+1)=5-x(1-2x)

    2x^2 + (2x-7x) -7 =5-x + 2x^2

    2x^2 -5x -7= 5- x + 2x^2

    0 = 4x +12

    -12 = 4x

    -3 = x

    the 2x^2 cancel out.

    equation 2

    the same but you just replace the &quot;=&quot;sign with &quot;&lt;&quot; sign so

    -3 &lt; x or if you reverse it

    3&gt;x


  4. 1.

      (2x - 7)(x+1) = 5-x(1 -2x)

      = 2x^2 - 5x -7 = 5 - x + 2x^2

      = 4x =  -12

      =  x = - 3

    2.

       (2x - 7)(x + 1) &lt; 5 - x(1 - 2x)

      =2x^2 - 5x -7 &lt; 5 - x +2x^2

      =4x&lt;  - 12

      = x &lt; -3

      

  5. hi

      1:  

      =&gt; 2(x)^2 +2x -7x -7 = 5-x+2(x)^2

                            2x-7x+x=5+7 ==&gt; -4x=12 ==&gt; x=-3

    2:

    =&gt; 2(x)^2+2x-7x-7&lt;5-x+2(x)^2

                      2x-7x+x &lt; 5+7

                      -4x   &lt;   12  

                       - x  &lt;  3

                         x  &gt;  -3

  6. The way I would do this is to multiply out the brackets on both sides, so with the first one, you would get

    2x(squared)-5x-7 = 2x(squared)-11x+5.  

    To both sides, i would add 7, to cancel out the minus seven on the right,  so you get

    2x(squared)-5x = 2x(squared)-11x+12.

    Then i would add 5x to both sides, to cancel out the minus 5x on the right, so you get

    2x(squared) = 2x(squared)-6x+12.

    This means that -6x=12, to make the expression true.

    Divide this by -6, and you get the answer,

    x = -2.

    As for the second one, it is the same process, just with a &lt; sign.

    I hope this has helped you.  

  7. (2x - 7)(x + 1) = 5 - x(1 - 2x)

    2x^2 + 2x - 7x - 7 = 5 - x + 2x^2

    2x^2 - 2x^2 - 5x + x - 7 - 5 = 0

    -4x - 12 = 0

    -4x = 12

    x = 12/-4

    x = -3

    (2x - 7)(x + 1) &lt; 5 – x(1 – 2x)

    2x^2 + 2x - 7x - 7 &lt; 5 - x + 2x^2

    2x^2 - 2x^2 - 5x + x - 7 - 5 &lt; 0

    -4x - 12 &lt; 0

    -4x &lt; 12

    4x &gt; -12

    x &gt; -3

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