How to solve (-9)-16 subtracting integers

Pls! does anybody know a shortcut for answering these types of questions in the future?

Danielle earns a 7.25% commission on everything she sells at the electronics store where she works. she also earns a base salary of $750 per week. what were her sales last week if her total earnings for the week were $1,076.25?

That table shows measurements (in invhes$ from cubes with different side lengths. which pairs of variables have a linear relationship? check all that apply