Question

giúp em vs ạ em cảm ơn

Answer 1

a)\(\Leftrightarrow\left|x+1,5\right|=4\)

\(\Leftrightarrow\left[{}\begin{matrix}x+1,5=4\\x+1,5=-4\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=2,5\\x=-5,5\end{matrix}\right.\)

c)\(\Leftrightarrow-14+21x=5+10x\)

\(\Leftrightarrow11x=19\Leftrightarrow x=\dfrac{19}{11}\)

Answer 2

\(b,\Leftrightarrow3^{x-2}\left(1+5\cdot3^3\right)=408\\ \Leftrightarrow3^{x-2}\cdot136=408\\ \Leftrightarrow3^{x-2}=3=3^1\Leftrightarrow x-2=1\Leftrightarrow x=3\)