Question

log5 ×=2
log0,4 ×=-1​

Answer 1

$log_{5}(x)=2\\x=5^{2};\\x=25;\\log_{0.4}(x)=-1;\\log_{\frac{2}{5}}(x)=-1;\\x=(\frac{2}{5})^{-1};\\x=\frac{5}{2}.$