Giải thích các bước giải:
Ta có:
\(\begin{array}{l}
a,\\
\left( {x - 8.25} \right).4 = 0\\
\Leftrightarrow x - 8.25 = 0\\
\Leftrightarrow x - 200 = 0\\
\Leftrightarrow x = 200\\
b,\\
\left( {x - 50} \right).4 - 3 = 97\\
\Leftrightarrow \left( {x - 50} \right).4 = 3 + 97\\
\Leftrightarrow \left( {x - 50} \right).4 = 100\\
\Leftrightarrow x - 50 = 100:4\\
\Leftrightarrow x - 50 = 25\\
\Leftrightarrow x = 50 + 25\\
\Leftrightarrow x = 75\\
c,\\
8.\left( {22 - x} \right) = 24\\
\Leftrightarrow 22 - x = 24:8\\
\Leftrightarrow 22 - x = 3\\
\Leftrightarrow x = 22 - 3\\
\Leftrightarrow x = 19\\
d,\\
\left( {x:3 - 3} \right).\left( {x:6 - 6} \right) = 0\\
\Leftrightarrow \left[ \begin{array}{l}
x:3 - 3 = 0\\
x:6 - 6 = 0
\end{array} \right. \Leftrightarrow \left[ \begin{array}{l}
x:3 = 3\\
x:6 = 6
\end{array} \right. \Leftrightarrow \left[ \begin{array}{l}
x = 9\\
x = 36
\end{array} \right.\\
e,\\
334 - \left( {x.3 + 20} \right) = 284\\
\Leftrightarrow x.3 + 20 = 334 - 284\\
\Leftrightarrow 3x + 20 = 50\\
\Leftrightarrow 3x = 50 - 20\\
\Leftrightarrow 3x = 30\\
\Leftrightarrow x = 30:3\\
\Leftrightarrow x = 10\\
g,\\
4x + 5x - x = 128\\
\Leftrightarrow x.\left( {4 + 5 - 1} \right) = 128\\
\Leftrightarrow x.8 = 128\\
\Leftrightarrow x = 128:8\\
\Leftrightarrow x = 16
\end{array}\)
