(Solved): A road perpendicular to a highway leads to a farmhouse located 9 mile away. An automobile traveling ...

A road perpendicular to a highway leads to a farmhouse located 9 mile away. An automobile traveling on the highway passes through this intersection at a speed of

. How fast is the distance between the automobile and the farmhouse increasing when the automobile is 5 miles past the intersection of the highway and the road? The distance between the automobile and the farmhouse is increasing at a rate of miles per hour.