Holly's favorite book is about Johnny Appleseed, the American pioneer who planted apple trees all across the country. Inspired b
y the story, Holly plants an apple seed in her backyard and tends the seed as it slowly grows into a tree. The proportional relationship between the age of Holly's apple tree (in years), x, and the height of the tree (in feet), y, can be modeled by the equation y = 1.5x. If the tree is 5.25 feet tall, how many years has the tree grown?
