5x(1 - 2x) - 3x(x + 18) = 0
=> 5x - 10x2 - 3x2 - 54x = 0
=> -13x2 - 49x = 0
=> x.(-13x - 49) = 0
=> x = 0
hoặc -13x - 49 = 0 => -13x = 49 => x = -49/13
Vậy x = 0, x = -49/13
\(5x\left(1-2x\right)-3x\left(x+18\right)=0\)
\(\Rightarrow x\left(5\left(1-2x\right)-3\left(x+18\right)\right)=0\)
\(\Rightarrow x\left(5-10x-3x+54\right)=0\)
\(\Rightarrow x\left(59-13x\right)=0\)
\(\Rightarrow\orbr{\begin{cases}x=0\\59-13x=0\end{cases}\Rightarrow\orbr{\begin{cases}x=0\\13x=59\end{cases}\Rightarrow}\orbr{\begin{cases}x=0\\x=\frac{59}{13}\end{cases}}}\)
\(5x.\left(1-2x\right)-3x.\left(x+18\right)=0\)
=>\(5x-10x^2-3x^2-54x=0\)
=>\(-49x-13x^2=0\)
=>\(x\left(-49-13x\right)=0\)
=>x=0 hoặc -49-13x=0
Nếu -49-13x=0
=>13x=-49
=>x=\(\frac{-49}{13}\)
Vậy x=0 hoặc x=\(\frac{-49}{13}\)