Respuesta :

apologiabiology
a(b-c)=ab-ac

(1/7)(1/3h-1/2)=(1/7)(1/3h)-(1/7)(1/2)=1/21h-1/14

now we gots
6 and 1/7+1/21h-1/14
rearange
6 and 1/7-1/14+1/21h
make common denom which is 14
6 and 2/14-1/14+1/21h
6 and 1/14+1/21h