



 
Maryanne, I am going to let t be time in minutes, starting at 3:25. Car 2 is travelling at 60 mph which is 1 mile per minute and car 1 is travelling at 3/4 miles per minute. My diagram is at some time t minutes after 3:25 when the cars are 40 miles apart. I is the intersection and it took 25 minutes for car 1 to reach P. What is the distance from I to P? Car 2 travels t minutes to reach R. What is the distance from I to R? What is the distance from P to Q? Triangle RIQ is a right triangle and the length of QR is 40 miles. What does Pythagoras theorem tell you about the lengths of the sides of the triangle? Solve for t. I hope this helps,  


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