Two cars start out at the same point and at the same time one starts driving north while the other starts driving east at a speed that is 10 mph faster than the car driving north. 12 hours after the cars start driving they are 600 miles apart. What was the speed of each car?
Let x be the speed of the first car in miles per hour. After 12 hours it will have gone 12x miles. The other car, driving east, has speed x+ 4. After 12 hours it will have gone 12(x+ 4) miles. Again by the Pythagorean theorem,
(12x)^2+(12(x+4)^2=600^2. Solve that equation for x.
