Question

$3^{2x-1}+3^{2x}=108$

Answer 1

($3^{2x} +3* 3^{2x} -108*3$ ) = $0$
$3^{2x} + 3* 3^{2x} -324 = 0$
Замена $3^{2x} =a$
$a^{2} +3 a^{2} =324$
$4a^{2} =324$
$a^{2} =81$
$3^{2x} =81= 3^{4}$
$x=2$