The first step here would be to distribute the parenthesis to the -6.
5 - 6a - 12 = 7 + a
Next, combine all like terms. This means that the constants will combine, thus making the next step easier.
- 6a - 7 = 7 + a
Now, subtract the negative seven from the other side of the parenthesis. When I say add the negative, I mean that the sign (-) will flip, turning into a positive.
- 6a = 14 + a
Now do the same with the a, except this time the a will be subtracted from the other side due to it's positive sign being flipped into a negative.
- 7a = 14
Now you divide both sides by - 7. Almost done!!!
- 7a / - 7 = 14 / -7
Finally the equation simplifies to:
a= -2
