A trucker drove 9 hours to deliver a shipment of lumber. Returing home with a lighter load, the trucker averaged 8 miles per hour faster than on the earlier trip. After 7 hours, the trucker was only 60 miles from the starting point. The equation 9 s equals 7 open parentheses s plus 8 close parentheses plus 60 models the situation, where s represents the speed traveling to the delivery site. What is the value of s, in miles per hour? ( explain your answer)

Step-by-step explanation:

We have 9s = 7(s + 8) + 60.

=> 9s = 7s + 56 + 60

=> 2s = 116

=> s = 58.

Therefore the trucker was travelling to

the delivery site at 58 miles per hour.

chemists are often responsible for designing a chemical reaction and analyzing the products obtained from it. one significant part of designing a chemical reaction is determining the amount of each reactant that is needed and the amount of each product that will be produced. in order to do so, chemists use stoichiometry, the quantitative relationships between reactants and products.