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    a, factorise the expression x^2 -10x+16
    b. hence or otherwise solve the equation 8^2y -10(8^y) +16

    i have managed to do a and i have the answer for b. i just don't know how to do the working out. Can anyone help me please.
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    x^2 = (x )(x )
    2 numbers that add to make -10 and times to make 16
    -8,-2
    -8-2=-10
    -8x-2=16
    so therefore = (x-8)(x-2)

    can u rephrase the second question is it (8^2)times Y-10 or (8^2Y)-10
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    (Original post by jamesgillian123)
    x^2 = (x )(x )
    2 numbers that add to make -10 and times to make 16
    -8,-2
    -8-2=-10
    -8x-2=16
    so therefore = (x-8)(x-2)

    can u rephrase the second question is it (8^2)times Y-10 or (8^2Y)-10
    it's 8 then the power 2y subtract 10(8 power of y) then +16
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    You're gotten x = 8, and x = 2 for the first equation.
    You can write the next as 8^y = u, then just replace the 8^y with the u, you'll get again 8 and 2 for the factorisation.

    Now 8^y = 8
    y = 1
    and 8^y = 2
    y = 1/3
 
 
 
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Updated: November 8, 2017
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