Question

làm giúp em ạ, a,b,c bài 9 khỏi làm ạ,!

Answer 1

Bài 10:

a) Ta có: \(\left(x+\dfrac{1}{5}\right)^2=9\)

\(\Leftrightarrow\left[{}\begin{matrix}x+\dfrac{1}{5}=3\\x+\dfrac{1}{5}=-3\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{14}{5}\\x=\dfrac{-16}{5}\end{matrix}\right.\)

b) Ta có: \(\dfrac{22}{9}-\left(x+\dfrac{1}{2}\right)^2=\dfrac{7}{3}\)

\(\Leftrightarrow\left(x+\dfrac{1}{2}\right)^2=\dfrac{22}{9}-\dfrac{7}{3}=\dfrac{1}{9}\)

\(\Leftrightarrow\left[{}\begin{matrix}x+\dfrac{1}{2}=\dfrac{1}{3}\\x+\dfrac{1}{2}=-\dfrac{1}{3}\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{-1}{6}\\x=\dfrac{-5}{6}\end{matrix}\right.\)