The stopping distance of a car is modeled by the function d = 0.05r(r + 2) where d is the stopping distance of the car measured in feet and r is the speed of the car in miles per hour. If skid marks left on the road are 75 feet long, how fast was the car traveling?

The car was moving approximately at a speed of 37.74 miles per hour.

Step-by-step explanation:

We are given the following in the question:

The stopping distance of a car is given by

where d is the stopping distance in feet and r is speed of the car in miles per hour.

The stopping distance is 75 feet, we have to find the speed of the car,

Putting d = 75 in the equation, we get,

Thus, the car was moving approximately at a speed of 37.74 miles per hour.

the surface area is 124cm²

step-by-step explanation:

length: 4cm

width: 9cm

height:   2cm

really really sorry if i'm

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