a: \(\Leftrightarrow\dfrac{5x-3}{6}-\dfrac{2x-1}{4}=\dfrac{4x+2}{7}-5\)
\(\Leftrightarrow14\left(5x-3\right)-21\left(2x-1\right)=12\left(4x+2\right)-420\)
=>70x-42-42x+21=48x+24-420
=>28x-21=48x-396
=>-24x=-375
hay x=125/8
b: \(\Leftrightarrow15\left(x-3\right)+2\left(4x-10.5\right)=12\left(x+1\right)+120\)
=>15x-45+8x-21=12x+132
=>23x-66=12x+132
=>11x=198
hay x=18
c: \(\Leftrightarrow\dfrac{6x+3}{4}-5=\dfrac{6x-2}{5}-\dfrac{3x+2}{10}\)
\(\Leftrightarrow5\left(6x+3\right)-100=4\left(6x-2\right)-2\left(3x+2\right)\)
=>30x+15-100=24x-4-6x-4
=>30x-85=18x-8
=>12x=77
hay x=77/12
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