Question

Answer 1

=>x+1/4=9/5 hoặc x+1/4=-9/5

=>x=31/20 hoặc x=-41/20

Answer 2

\(\left(x+\dfrac{1}{4}\right)^2=\dfrac{81}{25}\\ \Leftrightarrow\left(x+\dfrac{1}{4}\right)^2=\left(\pm\dfrac{9}{5}\right)^2\\ \Leftrightarrow\left[{}\begin{matrix}x+\dfrac{1}{4}=\dfrac{9}{5}\\x+\dfrac{1}{4}=-\dfrac{9}{5}\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x=\dfrac{31}{20}\\x=-\dfrac{41}{20}\end{matrix}\right.\)