Question

Answer 1

PT \(\Rightarrow x^2=\left(-\dfrac{3}{5}\right)^2+\dfrac{4^2}{25}=1\) \(\Rightarrow x=\pm1\)

  Vậy ...

Answer 2

 \(x^2-\dfrac{4^2}{25}=\left(\dfrac{-3}{5}\right)^2\) 

          \(x^2=\dfrac{9}{25}+\dfrac{16}{25}\) 

          \(x^2=1\) 

\(\Rightarrow x^2=1^2\) hoặc \(x^2=\left(-1\right)^2\) 

     \(x=1\) hoặc \(x=-1\)