what should I do I don't know if I did it right

Answer:
[tex]\frac{7}{8}[/tex]
Step-by-step explanation:
you first need to change the mixed number to an improper fraction
[tex]\frac{13}{8}-\frac{3}{4}[/tex]
then multiply the second fraction by 2 so that the denominator is the same in both fractions
[tex]\frac{13}{8} -\frac{6}{8}[/tex]
[tex]\frac{7}{8}[/tex]