Question

Giải các phương trình:

a) \(\left|2x\right|=x-6\)

b) \(\left|-3x\right|=x-8\)

c) \(\left|4x\right|=2x+12\)

d)\(\left|-5x\right|-16=3x\)

Answer 1

\(a,\left|2x\right|=x-6\)

\(\Leftrightarrow2x=x-6\)

\(\Leftrightarrow2x-x=-6\)

\(\Leftrightarrow x=-6\)

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\(b,\left|-3x\right|=x-8\)

\(\Leftrightarrow3x=x-8\)

\(\Leftrightarrow3x-x=-8\)

\(\Leftrightarrow2x=-8\)

\(\Leftrightarrow x=-4\)

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\(c,\left|4x\right|=2x+12\)

\(\Leftrightarrow4x=2x+12\)

\(\Leftrightarrow4x-2x=12\)

\(\Leftrightarrow2x=12\)

\(\Leftrightarrow x=6\)

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\(d,\left|-5x\right|-16=3x\)

\(\Leftrightarrow5x-16=3x\)

\(\Leftrightarrow5x-3x=16\)

\(\Leftrightarrow2x=16\)

\(\Leftrightarrow x=8\)