Question

função exponencial
9x=243

Answer 1

$9^x=243\\\\ (3^2)^x=3^5\\\\ 3^{2x}=3^5\\\\ 2x=5\\\\ \boxed{x=\frac{5}{2}}$

Answer 2

$9^x=243$
Só que:
9=3²
243=3^5
Substituindo:
$3^{2x}=3^5$
2x=5
x=5/2