Answer:
[A] d = 28 -2t; 1993
Step-by-step explanation:
You are given two points:
(d, t) = (0, 28) and (8, 12)
The two-point form of the equation for a line can be a good place to start. For points (x1, y1) and (x2, y2), it tells you the line's equation is ...
y = (y2 -y1)/(x2 -x1)·(x -x1) + y1
For the given points, this is ...
d = (12 -28)/(8 -0)·(t -0) +28
d = -16/8·t +28
d = 28 -2t
Then d=0 will be the case when t is ...
0 = 28 -2t
0 = 14 -t . . . . . . . . divide by 2
t = 14 . . . . . . . . . . .add t
This corresponds to the year 1979 +14 = 1993.
The equation and year match selection [A].
