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.

step-by-step explanation: so we look at the formula un = a + (n-1)d

un is the amount of seats

n is the nth term aka row number

a is the original sequence/row number

d is the difference between each term

so in this a=22 d=6 and n can remain as n because we are simply formjng a rule

lets put these in the equation

un=22+(n-1)(6)

this is your answer to part a

however

lets double check that this is correct, we'll try putting it into the second term

un=a+(n-1)d

u2=22+(2-1)(6)

u2=22+6

u2=28

as the question said the second row has 28 seats so now we know the formula we made is correct.

as for part b

un=a+(n-1)

its asking us to find a row with 100 seats.

remember un was the amount of seata so all we do is substitute this in.

un=100 a=22 d=6

un=a+(n-1)d

100=22+(n-1)(6)

so now we simplify to find n which is the row number.

100-22=22+(n-1)(6)-22

78=(n-1)(6)

78/6=(n-1)(6)/6

13=n-1

13+1=n-1+1

14=n

so now we know that in the 14th row there is 100 seats.

hope this and that you understood! its my first time using the app or anyone out on here : p its also me to revise so a bunch! ask more questions if you dont understand ☺