The school that micaela goes to is selling tickets to an annual dance competition. on the first day of ticket sales the school sold 7 senior citizen tickets and 8 student tickets for a total of $115. the school took and $40 on the second day by selling 6 senior citizen tickets and one student ticket. what is the price of one senior citizen ticket and one student ticket? show work

a = adult ticket price

s = student ticket price

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7a + 2s = 87

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4a + 6s = 74

4a = 74 - 6s  

a = 74/4 - (6/4)s

a = 37/2 - (3/2)s

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7a + 2s = 87

7(37/2 - (3/2)s) + 2s = 87

7(37/2) - 7(3/2)s + 2s = 87

(259/2) - (21/2)s + 2s = 87

(21/2)s - 2s = (259/2) - 87

(21/2)s - (4/2)s = 259/2 - 174/2

(17/2)s = 85/2

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s = 85/2(2/17)

s = 85/17

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s = $5

a = $11

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sine

step-by-step explanation:

, and

for

step-by-step explanation:

we can analyze the pattern at which the terms increase. let us denote , , , so that we can call

note the following:

the pattern: to get the next term value, we just add the next term number (e.g. 1st, 2nd, to the previous term value (term values are the given numbers in the question, 1, 3, 6, 10, 15,

from , to get to , we add

from , to get to , we add

etc.

we need to form a recursive formula, a formula that has the next term as a function of the previous term. so a possible recursive formula can be

, and for