Colleen’s parents recently purchased a ranch. The ranch raises horses, cows and sheep. Colleen’s parents want to breed Bernedoodles to help out around the farm. Since she has never raised puppies before, Colleen wants to learn as much about her new puppy as possible. In particular, she wants to know how much a Bernedoodle puppy weighs when it is born. To find out, Colleen decided to track the weight of her first puppy who was born just before they purchased the ranch. She found that her puppy grew steadily by about 73 grams each day, and she assumes that he has been doing so since he was born. Seven days after he was born, the puppy weighed 811 grams.

Your Task: Determine how much the puppy weighed the day he was born using three different representations of the puppy's growth: a graph, an x → y table, and write equations. Then, assuming the puppy will continue to grow at the same rate, determine when the puppy will weigh 3900 grams.