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    Help me solve these, answers must be in the form of natural logarithm or the exponent e.
    3^{2x-3} -7 = 0
    5^{3x-2} = 4

    I do have an answer but I can't get the same answer as the book.

    answers are

    \frac{3 ln (3) + ln (7)}{2 ln (3)}

    and

    \frac{2(ln(5) + ln(2))}{3ln(5)}
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    Bring the power down and take log7 to the other side:
    (2x-3)log3 = log7

    Expand brackets:
    2xlog3 - 3log3 = log7

    Take 3log3 to the other side:
    2xlog3 = log7 + 3log3

    Divide by 2log3 to get the x on its own:
    x = log7 + 3log3 / 2log3

    Same format for the other question.
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    Im such an idiot wow, my maths is so rusty after finishing a levels.
    thanks
 
 
 
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