What's the quickest way to find the limit of an equation?

Sasha delivers newspapers to subscribers that live within a 4 block radius of her house. sasha's house is located at point (0, -1). points a, b, c, d, and e represent the houses of some of the subscribers to the newspaper. to which houses does sasha deliver newspapers?

Find the cocordinatse of the point on y axis which is nearest to the point (-2,5)

Mrs. piazza invested 8000 in a certificate of deposit that pays 3% simple interest for 4 years. how much will be in mrs. piazza's account at the end of 4 years