9. Critical Thinking The palm tree on the left is 10 years old. The palm tree on the right is 8 years old. The trees grow at the same rate. a. Estimate the height y (in feet) of each tree. b. Plot the two points (x, y), where x is the age of each tree and y is the height of each tree. c. What is the rate of growth of the trees? d. Write an equation that represents the height of a palm tree in terms of its age.