a) \(3x+5=1-2x\)
\(\Rightarrow3x+2x=1-5\)
\(\Rightarrow5x=-4\)
\(\Rightarrow x=-\dfrac{4}{5}\)
b) \(4x\left(x-1-2x\right)2x+3=20\)
\(\Rightarrow8x^2\left(-x-1\right)+3=20\)
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c) \(3x\left(2x-5\right)-4\left(5-2x\right)=0\)
\(\Rightarrow3x\left(2x-5\right)-4\left[-\left(2x-5\right)\right]=0\)
\(\Rightarrow3x\left(2x-5\right)+4\left(2x-5\right)=0\)
\(\Rightarrow\left(2x-5\right)\left(3x+4\right)=0\)
\(\Rightarrow\left[{}\begin{matrix}2x-5=0\\3x+4=0\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=\dfrac{5}{2}\\x=-\dfrac{4}{3}\end{matrix}\right.\)
d) \(x^2-4x+4=25\)
\(\Rightarrow x^2-2\cdot x\cdot2+2^2=25\)
\(\Rightarrow\left(x-2\right)^2=\left(\pm5\right)^2\)
\(\Rightarrow\left[{}\begin{matrix}x-2=5\\x-2=-5\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=7\\x=-3\end{matrix}\right.\)
\(\text{#}Toru\)