How do you solve $23^x + 5 = 128$ ?

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Answer 1 · 2016-10-03T06:39:29

$x = ln(123)/ln(23) = log_23(123)~~1.535$

Using the property that $ln(a^x) = xln(a)$ , we have

$23^x+5 = 128$

$=> 23^x = 123$

$=> ln(23^x) = ln(123)$

$=> xln(23) = ln(123)$

$:. x = ln(123)/ln(23) = log_23(123)~~1.535$

How do you solve 23^x + 5 = 12823^x + 5 = 128?