How do I solve $2 xx 3^x = 7 xx 5^x$ ?

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Answer 1 · 2017-10-16T08:16:23

By arranging the equation. ( $x=-2.45$ )

Divide both sides by 2 first:

$3^x = 3.5times5^x$

Or:

$3^x / 5^x = 3.5$

x is approximately -2.445 (or say -2.45) (by trial and error).

$3^-2.45 = 0.0677$
$5^-2.45 = 0.0194$

that satisfy $3^-2.45 / 5^-2.45 = 3.5$

How do I solve 2 xx 3^x = 7 xx 5^x2 xx 3^x = 7 xx 5^x?