SOLUTION: you plant a tree at the start, it is 3 feet tall. after 4 years,it is 8 feet tall. assuming linear growth, predict its height after 15 years.

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Question 1164788: you plant a tree at the start, it is 3 feet tall. after 4 years,it is 8 feet tall. assuming linear growth, predict its height after 15 years.
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
let x= years and y=height. x is the independent variable and can be controlled, and y is dependent and depends on x. This is standard throughout math and statistics.
ordered pairs (0, 3) and (4, 8)
point slope formula y-y1=m (x-x1) m slope (x1, y1) point
slope is 5/4
y-3=(5/4)(x)
y=(5/4)x+3
so after 15 years y=(5/4)*15+3
=21.75 feet.