Question

3x-15=2x.(x-5)

 

Answer 1

Ta có: \(3x-15=2x\left(x-5\right)\)

\(\Leftrightarrow3\left(x-5\right)-2x\left(x-5\right)=0\)

\(\Leftrightarrow\left(x-5\right)\left(3-2x\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x-5=0\\3-2x=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=5\\2x=3\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=5\\x=\dfrac{3}{2}\end{matrix}\right.\)

Vậy: \(S=\left\{5;\dfrac{3}{2}\right\}\)

Answer 2

3x-15=2x(x-5)

⇔3(x-5)-2x(x-5)=0

⇔(x-5)(3-2x)=0

⇔x-5=0 hoặc 3-2x=0

1.x-5=0⇔x=5

2.3-2x=0⇔-2x=3⇔x=-3/2

phương trình có 2 nghiệm:x=5 và x=-3/2