Question

3√3x-5√12x+7√27x=28

Answer 1

\(3.\sqrt{3x}-5\sqrt{12x}+7\sqrt{27x}=28\\ \Leftrightarrow3\sqrt{3x}-10\sqrt{3x}+21.\sqrt{3x}=28\\ \Leftrightarrow\sqrt{3x}\left(3-10+21\right)=28\\ \Leftrightarrow\sqrt{3x}=2\\ \Leftrightarrow3x=4\\ \Leftrightarrow x=\dfrac{4}{3}\)

Answer 2

ta có \(3\sqrt{3x}-10\sqrt{3x}+21\sqrt{3x}=28\)

<=>\(14\sqrt{3x}=28\)

<=>\(\sqrt{3x}=2< =>x=\dfrac{4}{3}\)