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    So i need to factorise 2x^2+13x+15

    The way Ive been taught is 2 x 15 is 30, then use factors of 30.
    All the calculators for this say the factors you use are 3 and 10 but they dont add up into 15

    Where am I going wrong?
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    (Original post by Peterson957)
    So i need to factorise 2x^2+13x+15

    The way Ive been taught is 2 x 15 is 30, then use factors of 30.
    All the calculators for this say the factors you use are 3 and 10 but they dont add up into 15

    Where am I going wrong?
    ax^2+bx+c

    The two numbers you're looking for should multiply to give a\times c and add to give b.

    So in this case, the two numbers should add multiply to give 30 and add to give 13.
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    (Original post by Notnek)
    ax^2+bx+c

    The two numbers you're looking for should multiply to give a\times c and add to give b.

    So in this case, the two numbers should add multiply to give 15 and add to give 13.
    I think you mean

    So in this case, the two numbers should add multiply to give 30 and add to give 13.
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    (Original post by DFranklin)
    I think you mean
    Thanks, that was an unfortunate mistake.

    Peterson957 Sorry if that confused you. I've edited my post now.
 
 
 
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