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3/5 - x - 1/10 = 0

6/10 - x - 1/10 = 0

x = 5/10 = 1/2

[tex]\large\sf{} \dfrac{3}{5} - x - \dfrac{1}{10} \\ \\\large\sf{} \dfrac{6 - 1}{10} \\ \\\large\sf{} \dfrac{5}{10} \\ \\ \large\sf{} \dfrac{5 \div 5}{10 \div 5} \\ \\ \large\sf{}{\large\boxed{\boxed{  { \large \sf \dfrac{1}{2} - x }}}}[/tex]

[tex]{\large\boxed{\boxed{  { \large \sf Bons~Estudos }}}}[/tex]