a) \(\left(x-8\right)\left(x^3+8\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x-8=0\\x^3+8=0\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=8\\x^3=-8\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=8\\x=-2\end{matrix}\right.\)
b) \(\Leftrightarrow4x-3-x-5=30-3x\)
\(\Leftrightarrow3x-8=30-3x\)
\(\Leftrightarrow3x+3x=30+8=38\)
\(\Leftrightarrow x=\frac{19}{3}\)
a) \(\left(x-8\right)\left(x^3+8\right)=0\)
=> \(\left[{}\begin{matrix}x-8=0\\x^3+8=0\end{matrix}\right.\)
=> \(\left[{}\begin{matrix}x=8\\x^3=-8=\left(-2\right)^3\end{matrix}\right.\)
=> \(\left[{}\begin{matrix}x=8\\x=-2\end{matrix}\right.\)
b) (4x - 3) - (x + 5) = 3(10 - x)
=> 4x - 3 - x - 5 = 30 - 3x
=> 3x - 8 = 30 - 3x
=> 3x + 3x = 30 + 8
=> 6x = 38
=> x = 38 : 6
=> x = 19/3
