Given the geometric sequence whose 5th term is a5 = 54 and whose common ratio is r = 3, find the first term and write the explicit rule.

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Juanita wade's new car has an msrp of $28,902.11 including title and processing fees. the premier package which includes surround sound and dvd player costs three times the amount of the in-style package which includes leather seats and select wheels. the total cost of her new car was $34,290.08 which included the 6.5% sales tax. find the cost of the premier package to the nearest cent.

Triangles abd and ace are similar right triangles. witch ratio best explains why the slope of ab is the same as the slope of ac?