How do you solve $2^(x-3) = 5 ^ (x+7)$ ?

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Answer 1 · 2016-05-04T16:03:48

$=>x~~-14.5647" to 4 decimal places")$

Taking logs

$(x-3)ln(2)=(x+7)ln(5)$

$=>x-3=(x+7)ln(5)/ln(2)$

Let $ln(5)/ln(2)=A$

$x-3=(x+7)A$

$=>x-Ax=7A+3 larr$ Corrected from -3 Tony B

$=>x=(7A+3)/(1-A)$

$cancel(=>x~~-10.0259" to 4 decimal places")$

$=>x~~-14.5647" to 4 decimal places")$

How do you solve 2^(x-3) = 5 ^ (x+7)2^(x-3) = 5 ^ (x+7)?