The x intercept means the moment when the computer completely loses its value and becomes obsolete
x intercept is given by y = -300x + 3000 = 0, which implies x = 3000/300 = 10 years
For y = -300x + 3000 = 1500, we have x = 1500/300 = 5 years
Therefore, it takes 5 years for the computer value to drop a half and more 5 years to the computer became completely obsolete