Respuesta :

Take into account that the relation in between the age of the tree and its tall can be written as follow:

y = kx + 13

where x is the age, y the tall and k the constant of proportionality.

You can calculate the value of k by using the given information in the statement of the question:

k = 14 in/year

To determine what is the age of the tree when it is 97 in tall, solve the linear equation for x:

x = (y - 13)/k

replace y = 97 and k = 14

x = (97 - 13)/14 = 84/14 = 6

Hence, the tree is 6 years old when it is 97 inches tall