Question

Tìm x biết

a,\(\frac{x-1}{x+5}\)=\(\frac{6}{7}\)

b,\(^{\left(x-\frac{1}{2^{ }}\right)^2}\)+\(\frac{2}{9}\)=\(\frac{2}{3}\)

Answer 1

a)Ta có:

\(\frac{x-1}{x+5}=\frac{6}{7}\Leftrightarrow7\left(x-1\right)=6\left(x+5\right)\)

\(\Leftrightarrow7x-7=6x+30\)

\(\Leftrightarrow7x-6x=30+7\Leftrightarrow x=37\)

b) Ta có:

\(\left(x-\frac{1}{2}\right)^2+\frac{2}{9}=\frac{2}{3}\)

\(\Leftrightarrow\left(x-\frac{1}{2}\right)^2=\frac{2}{3}-\frac{2}{9}=\frac{4}{9}\)

\(\Leftrightarrow\left[{}\begin{matrix}x-\frac{1}{2}=\frac{2}{3}\\x-\frac{1}{2}=-\frac{2}{3}\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x=\frac{7}{6}\\x=\frac{-1}{6}\end{matrix}\right.\)