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    Hi everyone.

    I am looking for someone to explain this problem in a very ‘simple simon’ manner.
    Multiple 3x + 2y by x - y

    Firstly I have added the X’s together to give myself 3x squared + 2y. But my book without any explanation then shows me

    3xsquared + 2y squared 😕

    Any help will be appreciated
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    (Original post by Chris -power)
    Hi everyone.

    I am looking for someone to explain this problem in a very ‘simple simon’ manner.
    Multiple 3x + 2y by x - y

    Firstly I have added the X’s together to give myself 3x squared + 2y. But my book without any explanation then shows me

    3xsquared + 2y squared 😕

    Any help will be appreciated
    3x^2+2y^2 is not the correct final answer.

    From (3x+2y)(x-y), we can split either bracket - I'll choose the second - to get:

    (3x+2y)x - (3x+2y)y

    Note the minus sign, since it was -y.

    =(3x^2 +2xy) -(3xy + 2y^2)

    =3x^2 +2xy - 3xy - 2y^2

    And tidy up

    =3x^2 - xy - 2y^2
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    Name:  image.jpg
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Size:  500.0 KBHi thanks for you’re reply. Maybe if I had of been a little clearer from the start this would of helped more.

    This is the example in question. I am trying understand this but having no real luck of having it translated into something that I can understand. (Simple terms)

    Thank you for you’re help
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    Hi
    Please check my attachment. Hope thats helpful




    (Original post by Chris -power)
    Hi everyone.

    I am looking for someone to explain this problem in a very ‘simple simon’ manner.
    Multiple 3x + 2y by x - y

    Firstly I have added the X’s together to give myself 3x squared + 2y. But my book without any explanation then shows me

    3xsquared + 2y squared 😕

    Any help will be appreciated
    Attached Images
     
    • Study Helper
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    (Original post by Chris -power)
    Hi everyone.

    I am looking for someone to explain this problem in a very ‘simple simon’ manner.
    Multiple 3x + 2y by x - y

    Firstly I have added the X’s together to give myself 3x squared + 2y. But my book without any explanation then shows me

    3xsquared + 2y squared 😕

    Any help will be appreciated

    Well I can't see any "3xsquared + 2y squared" in that.

    In the first part of the question.
    3x+2y is firstly multiplied by x, giving one line.
    Then 3x+2y is multiplied by -y, giving a second line (lining up corresponding terms together).

    Then the two new lines are added together.
 
 
 
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