8. Ten friends go out for dinner. The total cost of the meals is $141. Some friends have three-course meals and the rest have two-course meals. Each
of the three-course meals costs $15 and each of the two-course meals
costs $12. The number of people who have three-course meals is x, so the
number of people who have two-course meals is 10 - x. How many three
course meals are possible?

2 three-course meals

20 three-course meals
e

7 three-course meals

5 three-course meals

7 three-course meals

Step-by-step explanation:

7 x 15= 105

141-105= 36

36/12= 3

7+3= 10

So total, there are 10 meals; 7 three-course and 3 two-course

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 ☺

cant see photo

step-by-step explanation: