`a)3x^2-2x=5(3x-2)`
`<=>x(3x-2)=5(3x-2)`
`<=>(3x-2)(x-5)=0`
`<=>[(3x-2=0),(x-5=0):}`
`<=>[(x=2/3),(x=5)`
Vậy `S={2/3;5}.`
`b)(2x-6)^2-x^2=0`
`<=>(2x-6-x)(2x-6+x)=0`
`<=>(x-6)(3x-6)=0`
`<=>(x-6)(x-2)=0`
`<=>[(x=6),(x=2):}`
Vậy `S={6;2}`
a, \(3x^2-2x=5\left(3x-2\right)\Leftrightarrow x\left(3x-2\right)-5\left(3x-2\right)=0\)
\(\Leftrightarrow\left(x-5\right)\left(3x-2\right)=0\Leftrightarrow x=5;x=\dfrac{2}{3}\)
b, \(\left(2x-6\right)^2-x^2=0\Leftrightarrow\left(x-6\right)\left(3x-6\right)=0\Leftrightarrow x=2;x=6\)
a)3x2-2x=5(3x-2)
⇒3x2-2x-5(3x-2)=0
⇒3x2-2x-15x+10=0
⇒3x2-17x+10=0
⇒3x2-15x-2x+10=0
⇒(3x2-15x)-(2x+10)=0
⇒3x(x-5)-2(x-5)=0
⇒ (3x-2)(x-5)=0
⇒ hoặc 3x-2=0⇒x=2/3
hoặc x-5=0⇒x=5
b) (2x-6)2-x2=0
⇒(2x-6-x)(2x-6+x)=0
⇒ (x-6)(3x-6)=0
⇒ hoặc x-6=0⇒x=6
hoặc 3x-6=0⇒x=2
Trả lời:
\(3x^2-2x=5\left(3x-2\right)\)
\(\Leftrightarrow x\left(3x-2\right)=5\left(3x-2\right)\)
\(\Leftrightarrow x\left(3x-2\right)-5\left(3x-2\right)=0\)
\(\Leftrightarrow\left(x-5\right)\left(3x-2\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x-5=0\\3x-2=0\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=5\\x=\dfrac{2}{3}\end{matrix}\right.\)
Vậy x = 5; x = 2/3 là nghiệm của pt.
b, \(\left(2x-6\right)^2-x^2=0\)
\(\Leftrightarrow\left(2x-6-x\right)\left(2x-6+x\right)=0\)
\(\Leftrightarrow\left(x-6\right)\left(3x-6\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x-6=0\\3x-6=0\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=6\\x=2\end{matrix}\right.\)
Vậy x = 6; x = 2 là nghiệm của pt.
