a)
\(x\cdot\left(x-4\right)=0\)
\(\orbr{\begin{cases}x=0\\x-4=0\end{cases}}\)
\(\orbr{\begin{cases}x=0\\x=0+4\end{cases}}\)
\(\orbr{\begin{cases}x=0\\x=4\end{cases}}\)
b)
\(375-\left(28+5x\right)=277\)
\(28+5x=375-277\)
\(28+5x=98\)
\(5x=98-28\)
\(5x=70\)
\(x=14\)
c)
\(2x+24=46\)
\(2x=46-24\)
\(2x=22\)
\(x=11\)
a) \(x\left(x-4\right)=0\Leftrightarrow\orbr{\begin{cases}x=0\\x=4\end{cases}}\)
b) \(375-\left(28+5x\right)=277\)
\(\Leftrightarrow5x=70\)
\(\Rightarrow x=14\)
c) \(5x-3x+24=46\)
\(\Leftrightarrow2x=22\)
\(\Rightarrow x=11\)
Bài giải
\(a,\text{ }x\left(x-4\right)=0\)
\(\Rightarrow\orbr{\begin{cases}x=0\\x-4=0\end{cases}}\Rightarrow\orbr{\begin{cases}x=0\\x=4\end{cases}}\)
\(\Rightarrow\text{ }x\in\left\{0\text{ ; }4\right\}\)
\(b,\text{ }375-\left(28+5x\right)=277\)
\(28+5x=375-277=98\)
\(5x=98-28=70\)
\(x=14\)
\(c,\text{ }5x-3x+24=46\)
\(2x+24=46\)
\(2x=22\)
\(x=11\)