The y-intercept of the trend line is (0,28). The slope of this line is
28-0
m = --------- = 2
14-0
Thus, the equation of the trend line, in variables K and J, is
K = 2J + 28
12 x 2 = 24 (Julio), 24 x 4 = 96 (David).
0 is the only degree that cannot work