Question

The braking distance, D, of a car is directly proportional to the square of its speed, v. When d=5, v=10

Answer 1

Answer:

         d = 245

Step-by-step explanation:

d is directly proportional to the square of a speed v

d = av²

5 = a•10²

5 = 100a

a = 0.05

d = 0.05v²

d = 0.05•70²

d = 0.05•4900

d = 245