a) \(\left(x-5.4\right)=0\)
\(\Leftrightarrow x-20=0\)
\(\Leftrightarrow x=0+20\)
\(\Leftrightarrow x=20\)
b) \(6x+4x=201\)
\(\Leftrightarrow10x=201\)
\(\Leftrightarrow x=201:10\)
\(\Leftrightarrow x=20,1\)
c) \(\left(x-4\right)\left(x-3\right)=0\)
\(\Leftrightarrow\orbr{\begin{cases}x-4=0\\x-3=0\end{cases}}\)
\(\Leftrightarrow\orbr{\begin{cases}x=0+4\\x=0+3\end{cases}}\)
\(\Leftrightarrow\orbr{\begin{cases}x=4\\x=3\end{cases}}\)
a/x bang 0 c/x bang 0
cau b hinh nhu sai de roi