Question

Bài 1: Tìm x biết

a) \(\left|-5x+3\right|\) - x + 5 = 4

Giúp mk vs, ai nhanh mk sẽ tick

Answer 1

a) \(\left|-5x+3\right|-x+5=4\)

th1: \(-5x+3\ge0\Leftrightarrow5x\le3\Leftrightarrow x\le\dfrac{3}{5}\)

\(\Rightarrow\left|-5x+3\right|-x+5=4\Leftrightarrow-5x+3-x+5=4\)

\(\Leftrightarrow-5x-x=4-3-5\Leftrightarrow-6x=-4\Leftrightarrow x=\dfrac{-4}{-6}=\dfrac{2}{3}\left(loại\right)\)

th2: \(-5x+3< 0\Leftrightarrow5x>3\Leftrightarrow x>\dfrac{3}{5}\)

\(\Rightarrow\left|-5x+3\right|-x+5=4\Leftrightarrow5x-3-x+5=4\)

\(\Leftrightarrow5x-x=4+3-5\Leftrightarrow4x=2\Leftrightarrow x=\dfrac{2}{4}=\dfrac{1}{2}\left(loại\right)\)

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