[tex]\bf \cfrac{7}{4}+\cfrac{1}{5x}-\cfrac{3}{2}=\cfrac{4}{5x}\implies \cfrac{7}{4}-\cfrac{3}{2}+\cfrac{1}{5x}=\cfrac{4}{5x}\implies \cfrac{7-6}{4}+\cfrac{1}{5x}=\cfrac{4}{5x}
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\cfrac{1}{4}+\cfrac{1}{5x}=\cfrac{4}{5x}\impliedby \textit{let's multiply both sides by 20x}
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20x\cdot \cfrac{1}{4}+20x\cdot \cfrac{1}{5x}=20x\cdot \cfrac{4}{5x}\implies 5x+4=16
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5x=16-4\implies 5x=12\implies x=\cfrac{12}{5}[/tex]