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#