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    ( 5x +2 ) 2

    = ( 5x + 2 ) (5x +2 )

    = (5x * 5x) + (5x * 2) + (2 * 5x) + (2 * 2)

    = (25x2) + (10x) + (10x) + (4)

    = 25x2 + 20x + 4
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    (Original post by the bear)
    for a rectangle you multiply the long side by the short side.

    for a square the long side and the short side are the same length.
    (Original post by RDKGames)
    That is not how area is calculated. Area has units like \mathrm{cm^2} which means that you multiply a length by some other length (hence length squared like cm squared). If you were to multiply length by itself 4 times, like (5x+2)^4, then you would end up with something different that is \mathrm{cm^4}.

    Anyway, the area of a square (or just any rectangle in general) is calculated by multiplying the length of the shape by its width.
    Ok I think I got it.

    The only thing is about this bit "Find an expression for the area" what does find an expression mean?
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    (Original post by Maths_English)
    Ok I think I got it.

    The only thing is about this bit "Find an expression for the area" what does find an expression mean?
    Expression is something like 23x+9 or \frac{x+1}{x-2}, so something that is not completely determined like saying the area is 1 or 10.
    Meaning that you want to give the area in terms of x here.
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    (Original post by RDKGames)
    Expression is something like 23x+9 or \frac{x+1}{x-2}, so something that is not completely determined like saying the area is 1 or 10.
    Meaning that you want to give the area in terms of x here.
    Ok so the answer should be 25x^2 + 20x + 4 correct?
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    (Original post by Maths_English)
    Ok so the answer should be 25x^2 + 20x + 4 correct?
    Yep.
 
 
 
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