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.