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The sum of two numbers is 86, and their difference is 20. find the two numbers

Find the roots of the equation below. x^2 - 6 + 9 = 0

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.