Question

equacao exponencial:7 elevado a 5-x=1sobre 343

Answer 1

$7^{5-x} = \frac{1}{343} \\ 7^{5-x} = 343 ^{-1} \\ 7^{5-x} = (7^{3} )^{-1} \\ 7^{5-x}= 7^{-3} \\ \\ 5-x=-3 \\ x=5+3 \\ x=8$