Respuesta :

glisintull
First, subtract 7 from both sides. 

5a = b - 7 

Now divide both sides by 5.

a = b - 7 / 5
you need to isolate the a
so...
subtract the 7 from both sides
5a = b - 7
then divide everything by 5
a = b/5 - 7/5

remember, what you do to one side of the equation you need to do the exact same to the other

hope this helps