\(5x+7,3=54,7\\ \Rightarrow5x=54,7-7,3\\ \Leftrightarrow5x=47,4\\ \Leftrightarrow x=47,4:5=\dfrac{237}{25}\)
Vậy \(x=\dfrac{237}{25}\)
\(x\times78,3=54+375,36\\ \Leftrightarrow x\times78,3=429,36\\ \Leftrightarrow x=429,36:78,3\\ \Leftrightarrow x=\dfrac{7156}{1305}\)
Vậy \(x=\dfrac{7156}{1305}\)