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Đáp án:
`1)` $\left[\begin{matrix} x = \dfrac{5}{3}\\ x=\dfrac{-5}{2}\end{matrix}\right.$
`2)` $\left[\begin{matrix} x = \dfrac{-1}{25}\\ x=1\end{matrix}\right.$
Giải thích các bước giải:
`2x.(3x−5)+15x=25 `
`⇔ 6x²−10x+15x−25=0`
`⇔ 6x^²+5x−25=0`
`⇔6x^² + 15x − 10x − 25=0`
`⇔ 3x(2x+5)−5(2x+5)=0`
`⇔ (3x - 5)*(2x + 5) = 0`
`⇔`$\left[\begin{matrix} x = \dfrac{5}{3}\\ x=\dfrac{-5}{2}\end{matrix}\right.$
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`25x^²−24x=1`
`⇔ 25x^²−24x−1=0`
`⇔ 25x^²−25x+x−1=0`
`⇔ 25x(x−1)+(x−1)=0`
`⇔ (25x + 1)*(x - 1) = 0`
`⇔` $\left[\begin{matrix} x = \dfrac{-1}{25}\\ x=1\end{matrix}\right.$
