Answer:
[tex]\frac{-1}{3}[/tex]
Step-by-step explanation:
[tex]\frac{-1}{13} - \frac{10}{39}[/tex]
Find common denominator for 13 and 39
common denominator is 39
rewrite fractions so they have the same denominator
[tex]\frac{-1}{13} = \frac{-3}{39}[/tex]
add them up
[tex]\frac{-3}{39} + \frac{-10}{39} = \frac{-13}{39}[/tex]
simplify/ put in the lowest terms
[tex]\frac{-1}{3}[/tex]