MAKING BRAINLIEST pls help me ​

Another type of subtraction equation is 16-b=7. explain how you would sole this equation then solve it.

Ebuka's monthly rent is $750. if ebuka pays the rent late, his landlord charges 4% interest per week that the payment is late. write a function that gives the total cost r(t), in dollars, of ebuka's rent if he pays it t weeks late.

What number is 7 units left of -15?