1) \(3x-2=6.\Leftrightarrow x=\dfrac{8}{3}.\)
2) \(x\left(x+8\right)-12=x^2+6x.\Leftrightarrow x^2+8x-12-x^2-6x=0.\\ \Leftrightarrow2x=12.\Leftrightarrow x=6.\)
3) \(\dfrac{3x+1}{6}=\dfrac{5x-2}{9}.\Leftrightarrow27x+9=30x-12.\\ \Leftrightarrow-3x=-21.\Leftrightarrow x=7.\)
4) \(\left(x-2\right)\left(2x+3\right)-x^2+4=0.\\ \Leftrightarrow2x^2+3x-4x-6-x^2+4=0.\Leftrightarrow x^2-x-2=0.\Leftrightarrow\left(x-2\right)\left(x+1\right)=0.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=2.\\x=-1.\end{matrix}\right.\)
1) \(3x-2=6\Rightarrow3x=6+2=\Rightarrow3x=8\Rightarrow x=\dfrac{8}{3}\)
2) \(x\left(x+8\right)-12=x^2+6x\)
\(1) 3x-2=6\\<=>3x=8\\<=>x=\dfrac{8}{3}\\ 2)x(x+8)-12=x^2+6x\\<=>2x-12=0\\<=>2x=12\\<=>x=6 \\3)\dfrac{3x+1}{6}=\dfrac{5x-2}{9} \)
\(<=>27x+9=30x-12 \\<=>3x=21\\<=>x=7 \\4)(x-2)(2x+3)-x^2+4=0 \\<=>(x-2)(x+1)=0\\<=>x=2\ hoặc\ x=-1\)
1) 3x+16=5x−29.⇔27x+9=30x−12.⇔−3x=−21.⇔x=7.3x+16=5x−29.⇔27x+9=30x−12.⇔−3x=−21.⇔x=7.
4) (x−2)(2x+3)−x2+4=0.⇔2x2+3x−4x−6−x2+4=0.⇔x2−x−2=0.⇔(x−2)(x+1)=0.(x−2)(2x+3)−x2+4=0.⇔2x2+3x−4x−6−x2+4=0.⇔x2−x−2=0.⇔(x−2)(x+1)=0.
⇔[x=2.x=−1.
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