If 1 grasshopper eats 10 blades of grass how many does 100 grasshoppers eat?

Which of the following expressions is equal to 2x^2+8

10 ! a train starts from grand city and travels toward belleville 388 miles away. at the same time, a train starts from belleville and runs at the rate of 47 miles per hour toward grand city. they pass each other 4 hours later. find the rate of the train from grand city.

Rewrite so the subject can be y in the formula d=m-y/y+n