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    Can someone please explain these to me, in a way that I can understand them? I have read the explanations over and over but I can't understand it. I am doing GCSE maths foundation. Can anyone please help me?
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    (Original post by Sharon Rennie)
    Can someone please explain these to me, in a way that I can understand them? I have read the explanations over and over but I can't understand it. I am doing GCSE maths foundation. Can anyone please help me?
    Which type of ones do you struggle with? Ones like 3(x+1) or (x+1)(x+2) or another kind?
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    (Original post by rayquaza17)
    Which type of ones do you struggle with? Ones like 3(x+1) or (x+1)(x+2) or another kind?
    All of them if I'm honest but especially the double brackets ones.
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    (Original post by Sharon Rennie)
    All of them if I'm honest but especially the double brackets ones.
    When you see things like (x+1)(x+2), you need to start off by looking at the first bracket and the first term. Here it is x, so we need to make a mental note of that. Then you look in the second bracket and work your way through multiplying everything by x and writing down every term you get when you do this. Then when you've reached the end of the right bracket, you need to move back to the left one and go to the next term, here it is a 1. Then you repeat the process of going to the right bracket and multiplying everything by the 1.

    I'm not sure if you have seen it, but this is a very good video explaining the process for lots of different problems: https://www.youtube.com/watch?v=1oYbcd6geWc

    But if after watching that and reading my explanation you are still not sure, try posting one of the problems you have attempted and we can work through it and see where you are going wrong and how to fix that.
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    if it helps, draw lines in from the 3 to both the things inside the brackets eg for 3(x+1) draw a line from 3 to x and 3 to 1. that way it helps you remember to multiply the 3 to both things inside the bracket. so the answer would be 3x+3


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    Multiply everything in the first bracket by everything in the second. A common way to remember this is FOIL- standing for First, Inside, Outside, Last.
    Ie multiply the first number/term in each of the brackets, the inside ie the middle two, the outside ie the first and last and finally last ie the second number in each bracket.

    For questions with different negative signs, remember that the sign belongs to the number in front of it, so for (y+6)(y-3) when you multiply the Outside part of FOIL you should do -3 x 6.

    If you want to convince yourself that the system works, try it with just numbers, eg (4+2)(5+6).
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    (Original post by rayquaza17)
    when you see things like (x+1)(x+2), you need to start off by looking at the first bracket and the first term. Here it is x, so we need to make a mental note of that. Then you look in the second bracket and work your way through multiplying everything by x and writing down every term you get when you do this. Then when you've reached the end of the right bracket, you need to move back to the left one and go to the next term, here it is a 1. Then you repeat the process of going to the right bracket and multiplying everything by the 1.

    I'm not sure if you have seen it, but this is a very good video explaining the process for lots of different problems: https://www.youtube.com/watch?v=1oybcd6gewc

    but if after watching that and reading my explanation you are still not sure, try posting one of the problems you have attempted and we can work through it and see where you are going wrong and how to fix that.
    thank you very much hun. I will watch it now.
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    (Original post by anon07079191)
    multiply everything in the first bracket by everything in the second. A common way to remember this is foil- standing for first, inside, outside, last.
    Ie multiply the first number/term in each of the brackets, the inside ie the middle two, the outside ie the first and last and finally last ie the second number in each bracket.

    For questions with different negative signs, remember that the sign belongs to the number in front of it, so for (y+6)(y-3) when you multiply the outside part of foil you should do -3 x 6.

    If you want to convince yourself that the system works, try it with just numbers, eg (4+2)(5+6).
    is that 9+8
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    Is that 9+8?
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    (Original post by Sharon Rennie)
    is that 9+8
    No you are over simplifying it.

    Doing it the normal way you would get:
    (4+2)(5+6) = 6 x 11 = 66 because first bracket is 6 and second is 11 and two things beside each other need to be multiplied.

    Using FOIL or expanding brackets you get:
    (4+2)(5+6) = 20 + 24 + 10 + 12 = 66

    So this shows that expanding brackets works.
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    The way i have been taught to do double brackets is by putting it into a nought and crosses grid kinda of. Kinda hard to explain over here but just put the each bracket on the outside sides and then times each bit together?

    So for example (x+2)(x+5)

    - x + 5
    x x² 5x
    +
    2 2x 10

    making x² + 5x + 2x +10
    x² + 7x + 10
 
 
 
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