How do you solve $6*17^a+4=20$ ?

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Answer 1 · 2018-03-22T03:09:00

$6*17^a = 16$

$3*17^a = 8$

$log_10 17^a =log_10 8 - log_10 3$

$a(log_10 17) = 0.426$

$a = 0.426/1.23$

$a = 0.346$

Checking,

$6*17^(0.346) + 4$

$6*2.67 + 4$

$16.02 + 4$

$20.02$ which is reasonably close to twenty.

How do you solve 6*17^a+4=206*17^a+4=20?