a: \(2x-\dfrac{2}{3}=\sqrt{\dfrac{25}{9}}\)
=>\(2x-\dfrac{2}{3}=\dfrac{5}{3}\)
=>\(2x=\dfrac{2}{3}+\dfrac{5}{3}=\dfrac{7}{3}\)
=>\(x=\dfrac{7}{3}:2=\dfrac{7}{6}\)
b: \(\left|2x+1,5\right|=\dfrac{5}{2}\)
=>|2x+1,5|=2,5
=>\(\left[{}\begin{matrix}2x+1,5=2,5\\2x+1,5=-2,5\end{matrix}\right.\)
=>\(\left[{}\begin{matrix}2x=2,5-1,5=1\\2x=-2,5-1,5=-4\end{matrix}\right.\)
=>\(\left[{}\begin{matrix}x=\dfrac{1}{2}\\x=-2\end{matrix}\right.\)
m:
\(\left|x-\dfrac{2}{5}\right|+\dfrac{3}{4}=\dfrac{11}{4}\)
=>\(\left|x-\dfrac{2}{5}\right|=\dfrac{11}{4}-\dfrac{3}{4}=\dfrac{8}{4}=2\)
=>\(\left[{}\begin{matrix}x-\dfrac{2}{5}=2\\x-\dfrac{2}{5}=-2\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=2+\dfrac{2}{5}=\dfrac{12}{5}\\x=-2+\dfrac{2}{5}=-\dfrac{8}{5}\end{matrix}\right.\)
a) 2x - \(\dfrac{2}{3}\) = \(\sqrt{\dfrac{25}{9}}\)
2x - 2/3 = 5/3
2x = 5/3 + 2/3
2x = 7/3
x=7/6
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