Answer:
d = -4
Step-by-step explanation:
3d – 4 + d = 8d – (-12)
3d - 4 + d = 8d + 12
4d - 4 = 8d + 12
(4d - 4d) - 4 = (8d - 4d) + 12
-4 = 4d + 12
-4 - 12 = 4d (+ 12 - 12)
-16 = 4d
-16/4 = 4d/4
d = -4
Answer:

Step-by-step explanation:
Set up the equation:
Since C(t) gives the number of cars purchased in the t-th year after 1998, then make the number of cars equal to 15 000 and solve for t - the year:
20t^2 = 15000
t^2 = 750
t = 
The year will be simply 1998 + 5 \sqrt{30}
Answer:
5 units
Step-by-step explanation:
The graph helps you measure it