If ${2^x}{.9^{2x + 3}} = {7^{x + 5}},$ then $x = $

JEE MATHEMATICS MCQ: SEQUENCE OF SERIES

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Application +4 | -1

{2^x}{.9^{2x + 3}} = {7^{x + 5}},

then

x =

View answer and explanation

Correct option: C

\frac{{5\log 7 - 6\log 3}}{{\log 162 - \log 7}}

Option C (

\frac{{5\log 7 - 6\log 3}}{{\log 162 - \log 7}}

) is correct because taking the logarithm of both sides and solving for x results in the given expression.

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