Investigators at a traffic accident used the function d(v) = 0.07v^2 + 0.9v, where v is the velocity of the car (in mph) and d(v) is the stopping distance of the car (in feet), to reconstruct the events leading up to a collision. From physical evidence, it was concluded that it took one car 220 feet to stop. At what velocity was the car traveling prior to the accident?
@-------College Al…

Question

Investigators at a traffic accident used the function d(v) = 0.07v^2 + 0.9v, where v is the velocity of the car (in mph) and d(v) is the stopping distance of the car (in feet), to reconstruct the events leading up to a collision. From physical evidence, it was concluded that it took one car 220 feet to stop. At what velocity was the car traveling prior to the accident?
      @-------College Al…

anonymous · Answer

solve 
$$.07v^2+0.9v=220$$ get 
$$v=50$$

anonymous · Answer

thank you @satellite73