SOLUTION: Could you please help me here A car leaves Seattle at 2 a.m. travelling south on I-5 at a constant rate of speed of 70 miles per hour. At 1 a.m. a car left Tacoma, forty miles

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Question 703085: Could you please help me here
A car leaves Seattle at 2 a.m. travelling south on I-5 at a constant rate of speed of 70
miles per hour. At 1 a.m. a car left Tacoma, forty miles south of Seattle, travelling south
on I-5 at a constant rate of speed of 50 miles per hour. When & where will the faster car
overtake the slower car
Answer by josgarithmetic(39617) (Show Source):
You can put this solution on YOUR website!
Analyze the positions and time for the two drivers. POSITION is more helpful than simply distance.

Use Seattle as a zero position and Tacoma as a +40 position. At start time (which is actually 1 A.M. here), Seattle car and Tacoma car are 40 miles apart, but Seattle car is at 0 and Tacoma car is at +40.
Formulas for Position:
Tacoma Car:
Seattle Car:
Where t is amount of time, NOT the time of day.

Now, the question of when will the fast (Seattle) car overtake the slow (Tacoma) car becomes, "At what quantity of t will their positions be equal?"

This means 2 hours after 1 A.M. Why after 1 AM? Because that was when any driving for this situation first begins.