Question

Tìm x biết

\(\sqrt{x+2}\) =\(\frac{5}{7}\)

Answer 1

\(\sqrt{x+2}\) = \(\frac{5}{7}\)

\(\Rightarrow\) x + 2 = \(\left(\frac{5}{7}\right)^2\)

\(\Rightarrow\) x + 2 = \(\frac{25}{49}\)

\(\Rightarrow\) x = \(\frac{25}{49}\) - 2

\(\Rightarrow\) x = \(\frac{-73}{49}\)

Vậy x = \(\frac{-73}{49}\)

Answer 2

\(\sqrt{x+2}=\frac{5}{7}\)

\(\Rightarrow x+2=\left(\frac{5}{7}\right)^2\)

\(\Rightarrow x+2=\frac{25}{49}\)

\(x=\frac{25}{49}-2=-\frac{73}{49}\)