Respuesta :

Step-by-step explanation:

-a-7a/8

-8a-7a/8

-15a/8

Hope it helps you

Answer:

Step-by-step explanation:

WE have to find the least common denominator and it is 8

[tex]-a =\frac{-a*8}{1*8}=\frac{-8a}{8}\\\\-a -\frac{7}{8}a=-\frac{8}{8}a-\frac{7}{8}a\\\\=\frac{-8a-7a}{8}\\\\=\frac{-15a}{8}\\\\[/tex]