\(a,2x+5=0\Rightarrow2x=-5\Rightarrow x=-\frac{5}{2}\)
\(b,x^2+5x=0\Rightarrow x\left(x+5\right)=0\)
\(\Rightarrow x=0\)hoặc x+5x=0
=>x=0 hoặc x=\(\frac{+}{-}5\)
\(\left[\frac{x+1}{2}\right]\left(2x-7\right)=0+\Rightarrow\frac{x+1}{2}=0\Leftrightarrow2x-7=0\)
\(\frac{x+1}{2}=0\Rightarrow x+1=0\Rightarrow x=-1\)
\(2x-7=0\Rightarrow2x=7\Rightarrow x=\frac{7}{2}\)
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