[tex]\text{Solve by turning it into a fraction and plugging in the value to x:}\\\\\frac{3x-1}{2x+1}\\\\\frac{3(6)-1}{2(6)+1}\\\\\frac{18-1}{12+1}\\\\\frac{17}{13}\\\\\text{You can't simplify the fraction any further, in which it'll conclude your answer}\\\\\boxed{\frac{17}{13}}[/tex]