a, \((\frac{3}{4}-x)^2=\frac{25}{16}\)
\(\Leftrightarrow (\frac{3}{4}-x)^2=(\frac{5}{4})^2\)
\(\Leftrightarrow (\frac{3}{4}-x)^2-(\frac{5}{4})^2=0\)
\(\Leftrightarrow (\frac{3}{4}-x-\frac{5}{4})-(\frac{3}{4}-x+\frac{5}{4})=0\)
b, \((2x -\frac{1}{4})^2=\frac{9}{25}\)
\(\Leftrightarrow (2x -\frac{1}{4})^2=(\frac{3}{5})^2\)
\(\Leftrightarrow (2x -\frac{1}{4})^2-(\frac{3}{5})^2=0\)
\(\Leftrightarrow (2x-\frac{1}{4}-\frac{3}{5})-(2x-\frac{1}{4}+\frac{3}{5})=0\)
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