Question

a.3x-6=0 

b.(x+1)(2x+4)=0

c.5x+3=2x+15

Answer 1

\(a,3x-6=0\\ \Leftrightarrow x=2\\ b,\left(x+1\right)\left(2x+4\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}x+1=0\\2x+4=0\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x=-1\\x=-2\end{matrix}\right.\\ c,5x+3=2x+15\\ \Leftrightarrow5x-2x=15-3\\ \Leftrightarrow3x=12\\ \Leftrightarrow x=4\)

Answer 2

\(a.3x-6=0 \)   \(\Leftrightarrow 3x=6\)  \(\Leftrightarrow x=2\)

\(b.(x+1)(2x+4)=0 \)

\(x+1=0\)   Hay  \(2x+4=0\)

\(x=-1\)      Hay  \(x=-2\)

\(c.5x+3=2x+15\)

\(\Leftrightarrow 3x=12\)

\(\Leftrightarrow x=4\)