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Which property was used to simplify the expression? 3c+9 +4c=3c+4c+9

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.

The stairs leading from the ground to the entrance of a plane forms a right triangle with the ground. if the distance of the stairs measures 22 feet and the ground distance measures 11 feet, how high is the entrance to the plane from the ground? which diagram represents this scenario? / 22ft © 22ft 11 ft 11 ft 22 it