Ireally dont understand this
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Hello i need some with trigonometric substitutions. [tex]\int\limits^a_b {x} \, dx[/tex]

Adriver from the university of florida women’s swimming and diving team is competing in the in ncaa zone b championships

Acar started driving from city a to city b, distance between which is 620 miles, at a rate of 60 mph. two hours later a truck left city b and started moving towards city a at a rate of 40 mph. how many hours after the truck's departure will the two meet?