Đáp án + Giải thích các bước giải:
`a//x(2x-9)=3x(x-5)`
`⇔2x^{2}-9x=3x^{2}-15x`
`⇔2x^{2}-3x^{2}-9x+15x=0`
`⇔-x^{2}+6x=0`
`⇔-x(x-6)=0`
`⇔` \(\left[ \begin{array}{l}x=0\\x-6=0\end{array} \right.\)
`⇔` \(\left[ \begin{array}{l}x=0\\x=6\end{array} \right.\)
Vậy `S={0;6}`
`b//0,5x(x-3)=(x-3)(1,5x-1)`
`⇔0,5x(x-3)-(x-3)(1,5x-1)=0`
`⇔(x-3)(0,5x-1,5x+1)=0`
`⇔(x-3)(-x+1)=0`
`⇔` \(\left[ \begin{array}{l}x-3=0\\-x+1=0\end{array} \right.\)
`⇔` \(\left[ \begin{array}{l}x=3\\x=1\end{array} \right.\)
Vậy `S={3;1}`
`c//3x-15=2x(x-5)`
`⇔3(x-5)=2x(x-5)`
`⇔3(x-5)-2x(x-5)=0`
`⇔(x-5)(3-2x)=0`
`⇔` \(\left[ \begin{array}{l}x-5=0\\3-2x=0\end{array} \right.\)
`⇔` \(\left[ \begin{array}{l}x=5\\x=\frac{3}{2}\end{array} \right.\)
Vậy `S={5;\frac{3}{2}}`
