4 × (-7)= -28 Your Answer: You owe your friend seven dollars. For every day that you do not pay him back, you owe him 7 more dollars. Day 1: (-7)×1= 7 dollars owed Day 2: (-7)×2=14 dollars owed Day 3: (-7)×3=21 dollars owed Day 4: (-7)×4=28 dollars owed