A gas station stands at the intersection of a north-south road and an east-west road. A police car is traveling toward the gas station from the west, chasing a stolen truck which is traveling north away from the gas station. The speed of the police car is 90 mph at the moment it is 5 miles from the gas station. At the same time, the truck is 12 miles from the gas station going 70 mph. a. At this time, The distance between the car and truck is decreasing at a rate of mph :
b. Is the distance between the police car and the truck increasing or decreasing?
c. When the truck is 4 miles from the gas station and the police car is 3 miles from the gas station, how fast is the distance between the police car and the truck changing?
d. At the same instant, how fast is the angle changing which has the police car as its vertex?

step-by-step explanation:

4.08%

step-by-step explanation:

560

step-by-step explanation:

giggidy

let's cover over the formula of the vertex:

y = a(x – h)^2 + k

in this formula, (h,k) are the vertex, always remember that the positive or negative value of the vertex is based on the sign it has.

for example, if the vertex is -3,-6 then both the x and y value would have the positive sign attached to it and if it were a positive x and y value, then a negative sign would be attached to it.

with that being said, for our problem the x value is a positive one so we are looking for a number with a negative sign next to it, in this case the first and second choice.

however, for the first answer choice it isn't quite part of the formula so we know that the answer choice correctly displays the x value.

to confirm, we can see if the -1 fits correctly with the second answer choice, and as mentioned above a negative number will have a positive sign attached to it. so, for our problem we can see that -1 has been changed to +1, so we can confirm that the second answer choice is correct.

hence, our final answer is y=(x - 1)^2 + 1