The length of a car’s skid mark in feet as a function of the car’s speed in miles per hour is given by l (s) =?

The length of a car’s skid mark in feet as a function of the car’s speed in miles per hour is given by l (s) = 0.046s ^2 − 0.199s + 0.264. If the length of a skid mark is 100 feet, find the speed in miles per hour the car was traveling.