Answer:
75.36 mph
Explanation:
The distance between the other car and the intersection is,
The distance between the police car and the intersection is,
(Negative sign indicates that he is moving towards the intersection)
Therefore the distance between them is given by,
The rate of change is,
Now finding
when
from (1) we have
The officer's radar gun indicates 25 mph pointed at the other car then,
when
from
From (2) we get
Hence the speed of the car is 