Question 249764
{{{6^(2x)-42*(6^x)+216=0}}}
This is a quadratic in 6^x
Sub z for 6^x --> {{{z^2 - 42z + 216 = 0}}}
(z - 6)*(z - 36) = 0
z = 6
z = 36
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Sub back:
6^x = 6
x = 1
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6^x = 36
x = 2