Question

tìm x :

5x.(x-3)-x+3=0

 

Answer 1

`5x.(x-3)-x+3=0`

`<=> 5x.(x-3)-(x-3)=0`

`<=>(x-3)(5x-1)=0`

\(\Leftrightarrow\left[{}\begin{matrix}x-3=0\\5x-1=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=3\\x=\dfrac{1}{5}\end{matrix}\right.\)

vậy \(x\in\left\{3;\dfrac{1}{5}\right\}\)

Answer 2

\(5x(x-3)-(x+3)=0 \)

\(\Rightarrow\)\(5x(x-3)-(x-3)=0\)

\(\Rightarrow\)\((x-3)(5x-1)\)

\(\Rightarrow\left(x-3\right)=0\) \(hoặc \) \(\left(5x-1\right)=0\)

\(\Rightarrow\) \(x=3 \) \(hoặc\) \(x= \)\(\dfrac{1}{5}\)

Answer 3

x∈{3;15}

Answer 4

x∈{3;15}