Try to make all the fractions have the same denominator.
Let's have them set to 14, since 2 and 7 are factors of 14.
1/2= 7/14 2/7= 4/14
Now replace them in the equation.
13/14- (7/14+4/14)
Combine like terms.
13/14- 11/14
2/14
Simplify.
1/7 is the answer.
I hope this helped!
